Head is to decapitate as arm is to what?

Solution 1:

I think the word you're looking for is amputate. A remote possibility is delimb, but it's apparently used mostly to describe the removal of branches (tree limbs).

A few more thoughts...

Here's Merriam-Webster's definitions of amputate and dismember.

As you can see, the former definition does stress the medical connection, though amputate can be used in other contexts as well. More interesting is the definition of dismember, which seems to suggest the amputation or severing of multiple limbs. In fact, that's what I intuitively think of when I hear the word dismember, which generally describes extraordinary violence.

In that spirit, dismember might not be the best choice for the OP, who asked,

What is the single word for removing a limb, specifically an arm?

In summary, I think either amputate or sever would work better. Sever would be the obvious choice if you want to escape the medical connotation. My feelings won't be hurt if you want to choose a new correct answer. ;)

Solution 2:

tl;dr: Use either of these, which pair like with like:

  1. In Star Wars: The Clone Wars, Christopher Lee’s character Count Dooku was decapitated, but not before he was dismembered.

  2. In Star Wars: The Clone Wars, Christopher Lee’s character Count Dooku was beheaded, but not before he was belimbed.

Either is perfectly understandable in that context.

Deviant Art portrayal of the famously dismembered Black Night from Monty Python and the Holy Grail

Image credit Cajun Pro @ Deviant Art


Decapitate, Dismember

You might try to get away with disarm if you were just joking around, but the formal term is dismember, which per the OED means:

  1. trans. To deprive of limbs or members; to cut off the limbs or members of; to tear or divide limb from limb. (In quot. 1697, to castrate.)

    • 1697 Potter Antiq. Greece ɪɪ. iii. (1715) 204 ― Some were so rigid Observers of the rules of chastity that··they dismember’d themselves.
    • 1855 Macaulay Hist. Eng. IV. 286 ― To be torn with redhot pincers, smeared with melted lead, and dismembered by four horses.

    b. transf.

    • 1830 J. G. Strutt Sylva Brit. 93 ― Its branches are so tough as to withstand the fury of gales that would dismember most other trees.

    c. To carve: said in reference to herons and some other birds. Obs.

    • 1804 Farley Lond. Art Cookery (ed. 10) 293 ― To dismember a Hern. Cut off the legs, lace the breast down the sides.
  2. fig. To divide into parts or sections, so as to destroy integrity; to cut up, cut to pieces, mangle, mutilate: in recent use chiefly, To divide and partition (a country or empire)

  3. To cut off, sever from the body (a limb or member).

    • 1675 Traherne Chr. Ethics xx. 319 ― A hand, or foot dismembred from the body.

If you are attempting parallelism of form, then dismember matches decapitate in that both are multi-syllable words derived from Latin. The OED etymology entry for dismember says:

Etymology: a. OFr. desmembre‑r (11th c. in Hatz.-Darm.), mod.Fr. démembrer = Pr., Sp., and Ital. desmembrar, Ital. di)smembrare, med.L. dismembrāre and dēmembrāre, f. dis- 4, de- 6 + membrum limb.

So a member means any limb. In the 1697 citation provided above, it means the male member.

The gruesome Wikipedia entry on dismemberment starts off with the following text:

Dismemberment is the act of cutting, tearing, pulling, wrenching, or otherwise removing the limbs of a living thing. It has been practised upon human beings as a form of capital punishment, can occur as a result of a traumatic accident, or in connection with murder, suicide, or cannibalism. As opposed to surgical amputation of the limbs, dismemberment is often fatal to all but the simplest of creatures.

That leads to a sentence like this:

  • In Star Wars: The Clone Wars, Christopher Lee’s character Count Dooku was decapitated, but not before he was dismembered.

Behead, Belimb

However, if you are looking for a word to pair with behead, then dismember is arguably too ornate. As discussed in Why is it “behead” and not “dehead”?, we didn’t need a Latinate de- there because we were using the Germanic prefix be- in the ancient way that means to bereave someone of something. In the OED entry for be-, they mention belimb:

An ancient application, no longer in living use, was to express the sense of ‘bereave of,’ as in behead, belimb, etc.”

Wiktionary gives belimb the following sense:

(transitive, obsolete) To cut off a limb or limbs; dismember; mutilate; disfigure.

Like the verb beland meaning to deprive someone of their lands (destierro in Spanish), the verb belimb for depriving someone of a limb is no longer used much in current English. However, given the appropriate context and setup, this old wold could be easily dusted off and use.

The verb belimb was used in Middle English, where like all words at that time it enjoyed a wealth of spelling variants. The entry in the University of Michigan’s Middle English Dictionary gives this sense for belimb:

To sever limb from limb; esp., to mutilate or maim (an enemy, an offender) by cutting or tearing off a part of his body; refl. mutilate oneself.

Belimb has various Middle English citations, including one from Robert of Gloucester’s Chronicle, where King Knut “out of wrath had hostages belimbed”:

þeruore þe kẏng Knout wẏþ hem was so wod wroþ,
And vor wraþþe let bẏlẏme her ostages þat were.

When you place it in the context of beheaded, belimbed is completely understandable.

  • In Star Wars: The Clone Wars, Christopher Lee’s character Count Dooku was beheaded, but not before he was belimbed.

If you aren’t trying for literary parallelism, perhaps this does not matter so much.


Brachiotomy

Another rather ugly term with a related medical sense is brachiotomy, which the Free Dictionary gives as:

  1. Amputation of an arm to effect vaginal delivery, a procedure with no legally viable indications in modern obstetrical practice.
  2. Forequarter amputation.

Even though sense 2 is close, its overtone of medicate amputation and its fancy classical roots make it unsuitable for most normal discourse.


Severed

If you wanted to use the same verb for both bodily separations, you could do worse than choose the pedestrian sever, perhaps like this:

  • In Star Wars: The Clone Wars, Christopher Lee’s character Count Dooku arm was severed from his body right before his head was.

Solution 3:

I agree dismembered would work best in the context of the original question, but my first thought in the vein of head/decapitated was...

Sever, as in a severed limb.

Sever
To separate (a part) from the whole, as by cutting or the like; to divide into parts, especially forcibly; cleave.

Source: Dictionary.com http://dictionary.reference.com/browse/sever

Solution 4:

Try dismember.

It means to cut one or more limbs off a person or animal, for example when butchering a carcass. In most applications, one does not cut off a single limb without cutting off them all, so this word presents some challenges.

It is not an exact match for what you want. Unless otherwise specified, "Richard was dismembered by the cheeky axeman" would most likely be taken to mean the axeman cut off ALL Richard's limbs, and maybe his head as well, since member is a rather general term for any bodily protruberence -- including the ribald ones. However if you first said explicitly that only Richard's left arm was severed, then you could refer back to that event using the word "dismember" with no confusion.

Another drawback of using this word unqualified, is that it can also be a metaphor for disfigure. Clearly a dismembered human is disfigured, but a human may be disfigured without exactly being dismembered.

The word amputate usually sees use in a medical context. Unqualified, "Richard's limb was amputated" means that it was in his best interest that the limb be removed -- whether he agreed at the time or not. For example the limb had been destroyed by fire and needed to be removed before it caused blood poisoning, or the limb was broken beyond repair, and would only cause him pain and discomfort if it remained attached.

While technically (whatever that means), an amputation may only be performed on a limb, your reader may not know this. Removing the appendix is usually called an apendectomy, but most people would probably see no error with "They amputated her appendix".