By any other name

What’s in a name? That which we call a rose
By any other name would smell as sweet;
So Romeo would, were he not Romeo call’d,
Retain that dear perfection which he owes
Without that title. Romeo, doff thy name,
And for that name which is no part of thee
Take all myself.

— William Shakespeare

Juliet is ready for level two sword study. 

There is some confusion regarding the terms tachi, katana, uchigata, naginata, naginata naoshi, tanto, sunnobi tanto, wakizashi, and ko-wakizashi.

The NBTHK lacks some consistency when they paper some of these blades, so I figured I would go through everything at length.

What you’re going to do with it is what you need to focus on

Basically, these swords and the various related types of weaponry are named by their intended use. If you have a blade in tachi mounts, it is a tachi. If you take it and put it into katana mounts it is a katana. The difference is in how they’re worn. Tachi is slung from the waist and rests edge down, and a katana is put through the belt. 

There are also subjective and objective criteria that apply as sometimes the measurement will cause a blade to be reclassified even though the intention was to serve a certain purpose.

Before we get into it, multiples of 30 cm are magical because they roughly correspond to 1 shaku which is the old Japanese unit close to a foot. Currently this is 30.3 cm but historically may have been up to about 35 cm, before getting into the problems all cultures had with standardizing units. 

I’ll run through the various cases. If I missed anything, feel free to comment and I’ll add to the lists.


Specifically a tachi is a style of mounting that has the sword slung edge down. You get here by:

  • currently residing in tachi mounts
  • being made intended for tachi mounts, and retaining the signature on the nakago, or the majority of the nakago, or an ubu nakago regardless of signature

Tachi are generally signed on the opposite side to katana, but this is not a strict rule. Japanese swords were made mostly to have the maker’s signature face outwards. But there are counter-examples of katana and tachi both that have the signature facing in the opposite direction on a regular basis (i.e. the maker always signed on the opposite side to tradition). As well, some makers like Aoe Tsugunao made tachi and signed on either side. So we really need to look at the signature placement on a case by case basis to use it in part of determining what kind of sword we’re dealing with.

We can determine the intention of mounting in tachi koshirae by the following observations (outside of trivial case of having the mounts on hand):

  • signature placement as qualified above
  • curvature in the nakago: katana nakago are generally made straight or straighter than tachi (i.e. this needs a judgment call)
  • period of manufacture: before the Muromachi period, long swords were made as tachi by rule and katana by exception, and after Muromachi, the reverse is true. At least by what has been preserved for us, we apply this as a rule of thumb.
  • placement of the mekugiana: Tanobe Michihiro sensei has said that “four fingers means tachi, three fingers means katana.” Basically, tachi mekugiana are usually placed closer to the center of the nakago (four finger widths from the machi) than katana mekugiana (which are about three fingers from the machi)

The shape of the blade does not determine if it is a tachi or a katana because it doesn’t tell us anything about the mounts. The mounts are the key to assessing what kind of blade we’re dealing with. 

Tachi subtypes

In addition to the above, a tachi can be additionally described as a kodachi if it is below 60 cm in length and all of the tachi criteria apply. 

This basically means “small tachi.”

The opposite is odachi or nodachi which is a “big tachi” that is made so big that it might take two people to take it out of the mounts, or requires the saya to be dropped as part of the draw. Think about it: if the blade is longer than your wingspan, you cannot physically draw the blade and keep a hand on the koshirae. As far as I know there is no measurement requirement for this assessment, but that is probably a rule of thumb to think of if you want to call something an odachi.


This is a fairly generic sword description. You get here by:

  • currently residing in katana mounts
  • being a tachi that lost most or all of its original nakago and certainly its signature
  • being a naginata that has been cut down and reshaped for use in katana mounts… specifically would be a naginata-naoshi katana in this case
  • being made specifically for use in uchigatana style mounts (i.e. edge up through the belt) … note that this style of use goes all the way back to the Kamakura period, and maybe earlier, though it becomes quite popular in the Muromachi period (katana become more popular than tachi at this point, or are at least preserved more frequently).
  • In addition, you should be of a measurement above 60 cm by modern assessment. Blades that are floating plus or minus a few millimeters around this mark could have been considered wakizashi by Edo period measuring.

Katana subtypes

If a blade is signed and fits the criteria for a katana, excluding the length condition, it might be called an uchigatana. Uchigatana is generally synonymous with katana, but in practice these terms may be used on small katana that come from periods before katana became standard. 

But don’t be surprised if someone just says that it’s a wakizashi because it’s below 60 cm. This is a modern assessment that requires no subjectivity.

If you are confused, don’t worry, as it is indeed confusing.

They used to call tanto by the name katana too. 

There are some instances of swords that may have been made for dual use as tachi or katana. Considering the first three generations of the Shinto Hizen smiths (Tadayoshi I, Tadahiro, and Tadayoshi III), about 15% of these have two mounting holes which is unusually high (compared to say Shinkai which has about 5%). Some number of these extra holes were made simply for remounting a blade later on in its life. However these Hizen blades often show a second mekugiana placed toward the end of the nakago for use in koshirae with two mekugi, and some of these examples are clearly set up for katana and tachi mounts.


Whether or not these were made like this at the shop, is open for debate. One thing that I have been wondering for a while, is why do the Hizen smiths sign tachi-style on their katana? This is potentially one answer, that the blades were all made so that they would be appropriate to use formally in tachi mounts. When the blade was finished, the buyer would choose how he wanted to mount the blade, either as a tachi or katana or both. The blade would then have been most suitably laid out for formal use and in casual use would have been around backwards. 

The Hizen smiths signed their wakizashi as would be expected, in katana-style with the mei facing out when the blade was worn through the belt. And of course nobody would be mounting one of those as a tachi so it would be known at the time of making how that blade was to be used.

It’s possible that the first generation did this and the others followed. I see an unusual amount of extra holes going up through the third generation indicating that tachi mounts were in play for many of them. At this point and onward, this signing style would just have become tradition for the school.

I confess that this is just my theory and speculation, as I have been trying to figure out practical reasons for the Hizen school to sign in this manner, and it happens to also explain the additional holes found on so many Hizen blades.


This brings us to the humble wakizashi. The wakizashi’s name means companion sword and this may have two meanings. First is that it is the secondary sword to a katana in a daisho pairing. More on daisho later. As such it is the companion to the katana.

Also in the Edo period, samurai who wore the daisho would put the katana on a rack indoors and retain the wakizashi. As such the wakizashi is the blade that stayed with them all the time. It’s also the blade you’d use for seppuku.

With Edo period sword laws, merchants could not use a longer sword so used wakizashi that had no matched katana, if they wanted a weapon.

Without the concept of the daisho it’s hard to say that the concept of the wakizashi is valid. This is why short katana from the Kamakura period might still be called katana by an author today. Basically the maker had no concept of wakizashi so we know the intent of that blade made in the 13th century had little to do with 17th century social regulations. So when you name that short older blade as a kodachi, wakizashi or katana, you will be taking either a metric assessment of it by length or else a practical use assessment as the maker and first user of the blade did.

Wakizashi by modern concepts are 30 cm to 60 cm in length.

Before the daisho we have a type of blade that we call a wakizashi because it falls into this spectrum of lengths, or is sometimes called a ko-wakizashi or a sunnobi tanto. These are all hirazukuri  (flat blades, no shinogi ridge) made in the Nanbokucho or Muromachi periods. 

Their intent was to be a backup blade to either a naginata or an odachi or to be worn solo. Some of this is speculation because we just don’t have a lot to go on now other than old paintings. But basically they are taking the role of large shaped tanto, and are only wakizashi by measurement rules or social use rules of the Edo period to the present.

Some of these blades can be quite long for a tanto and deeply curved. For example, 45 cm in length: twice the length of some Kamakura period tanto and these have changed enough to be their own thing most likely. Some are close to 30 cm, just slightly over the modern measurement that would determine tanto or wakizashi, and it is truly something that has zero practical difference when you’re talking about 29.9 cm vs. 30.1 cm. But we need to basically draw a line somewhere, so though these are both clearly tanto by use, we call one a wakizashi in order to have some kind of objective assessment. 

As a side note, many of these ko-wakizashi of the Nanbokucho period were made with very stubby nakago. The reason for this eludes me completely. It also seems to have eluded people of later periods because it is a very frequent modification to those blades that the machi is moved up to make a longer nakago. 

Also bear this in mind then, that in a practical sense there is a large pricing difference between a katana and a wakizashi (the katana being more valuable). A blade that is very close to the 60 cm mark and just above, can be described now by a dealer as a katana, though in the past, and by its intended manufacture, it may have been a wakizashi due to variations in the length of the shaku and the difficulty in making standard units. So just because something is a katana now or a wakizashi on the papers, doesn’t mean that historically that’s what this thing was. Use your judgment.


These are basically knives. The original name for them was indeed katana and their use goes all the way back to the Kofun period. As one may expect, a knife is easy to carry, and easy to use, and has been practical since the stone age. So we don’t expect that swords should predate knives in any culture.

The most frequent and well known examples that survive are from the Kamakura period, around about 1280 AD they suddenly come into vogue. Some authors say that tanto became popular at this period in time, but my opinion is that this is selection bias. I think before this period in time, they were made but not preserved as high quality art items, or luxury items, or superior weapons. We know the early Awataguchi school made these as there are signed Hisakuni tanto that exist and were high quality.

Anyway by modern assessment a tanto is a blade that has an edge less than 30 cm.

Tanto subtypes

There are various shape-based modifying terms, but the three we care about here are metezashi, furisode and sunnobi.

metezashi is a tanto that is signed on the opposite side and maybe has a curved nakago. This type of tanto is meant to be worn on the back side of the hip. A tanto worn on the back cannot be blocked from the draw during frontal grappling. As a good bushi you are keeping your opponent in front of you, but if he manages to get inside your polearm range or your sword range, these weapons become useless. Should he grapple you and use a tanto you will be helpless if your tanto is in the front of your belt because his body can be used to prevent the draw. 

The solution then is the metezashi which is worn on the back hip, so you can reach behind yourself and grab it even if you’re body to body with your opponent. The curved nakago we see on some tanto may be similar to a pistol grip and ease the draw from behind.

Furisode type tanto are more of a classification of the nakago. There is an impression that the furisode nakago refers to a curved nakago, and this is not correct. The name refers to the long sleeve of a scholar or priest’s garment and any longish appearing, tapering nakago can be described as furisode. The practicality of such a nakago is leverage at the point.

Sunnobi is another misused term. People in the west have used it to cover tanto that are just over the 30 cm long. These are indeed sunnobi tanto but the cutoff is actually at 0.85 shaku. This is 25.5 cm. Again, noting the variance of historical measurements and standards, the exact cutoff could vary. The point I am making is just that any unusually long tanto is probably going to qualify as sunnobi, not just those over 30 cm.


Now we are getting into the fun part. The naginata is a polearm, roughly equivalent to the European halberd. Without the koshirae, a blade on a long nakago made to mount in a pole is always a naginata.

Western habit is to call a naginata that has a katana style kissaki a nagamaki

This is incorrect.

The term nagamaki means “long wrapping” and refers to a type of pole that is wrapped over the handle. Extant examples are hard to come by. Below is one that was made as such but lost its wrapping. These are made with shorter poles than standard naginata and generally the pole is equal to or shorter than the length of the blade. It is also possible that such a tsuka on these koshirae may have no wrapping. It’s still a nagamaki if the koshirae takes this form.

If you lose this koshirae, you no longer have a nagamaki. You have a naginata. 

When you shorten a naginata for wearing as a sword, it is a modified naginata and called a naginata naoshi. If the head of the naginata was excessively flared, it may be cut off to straighten it during this process. 

Depending on the length you will get a naginata naoshi katana or a naginata naoshi wakizashi. Whether it was originally a nagamaki or not, this is what it is now. 

Making things a bit more confusing, a naginata naoshi katana may be just referred to as a katana by the rules above. This does not stop it from being properly described as a naginata naoshi katana. 

Similarly, if your papers just say katana you need to use your level two skills and determine if it is really a naginata naoshi katana. It may be. Sleuth it out.


A ken is generally a small ritual knife with symmetrical shape and two edges, sometimes leaf shaped or with a ridge in the middle.

The word tsurugi can refer to ken as well, as it ends up being the same kanji, but I think would not be used on the smaller ones.

The ken takes its shape from the sword of Fudo Myoo and is a religious implement that may not have been meant for use (though it is entirely functional). It can be of any length as well, though we are more familiar with the tanto length items from the Kamakura period, such as this Senjuin ken which is 26.7 cm.

As we go back in time we can find bigger ken, such as this Heian period ken which is 62 cm and Kokuho.

There is also this Juyo Bunkazai ken that is 92.9 cm.

The proper koshirae for a ken as seen above includes a vajra as the tsuka. 

Yari and Yanone

A yari is a spear, and sometimes it’s possible to find a spearhead that has been cut off to use as a tanto. This is pretty unusual and I am not sure exactly what to call such a thing. 

Yari teach us a lot about weapons because they are not held in really high regard generally or sought after by most collectors. Yanone (arrowheads) as well generally don’t have any special dispensation, though both of these items at the highest end are as artistic as any others and require a lot of work. 

There are only 63 Juyo Token yari out of the 13,000 or so Juyo items and only one Tokuju which reflects this bias. There are two Juyo Bunkazai but one of these is Kofun period (around 1,500 years old) and the other is Heian period (around 1,200 years old) so the age is counting for a lot here. There is in addition an Umetada Myoju yari which is Juyo Bijutsuhin and Juyo Bunkazai.

The situation for yanone is even worse as there are none with any particular rankings.