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arm¹

(ärm)

1. An upper limb of the human body, connecting the hand and wrist to the shoulder.

2. A part similar to a human arm, such as the forelimb of an animal or a long part projecting from a central support in a machine.

3. Something, such as a sleeve on a garment or a support on a chair, that is designed to cover or support the human arm.

4. A relatively narrow extension jutting out from a large mass:an arm of the sea. See Synonyms at branch.

5. An administrative or functional branch, as of an organization.

6. Power or authority:the long arm of the law.

7. Sports The skill of throwing or pitching a ball well.

Idioms:

an arm and a legSlang

An excessively high price:a cruise that cost an arm and a leg.

arm in arm

With arms linked together:They walked across the beach arm in arm.

at arm's length

At such a distance that physical or social contact is discouraged:kept the newcomer at arm's length at first.

with open arms

With great cordiality and hospitality.

[Middle English, fromOld Englishearm; see ar- in the Appendix of Indo-European roots.]

armed(ärmd)adj.

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arm1

arm²

(ärm)

1. A weapon, especially a firearm: troops bearing arms; ICBMs, bombs, and other nuclear arms.

2. A branch of a military force: infantry, armor, and other combat arms.

3. arms

a. Warfare: a call to arms against the invaders.

b. Military service: several million volunteers under arms; the profession of arms.

4. arms

a. Heraldry Bearings.

b. Insignia, as of a state, an official, a family, or an organization.

v. armed, arm·ing, arms

v.intr.

1. To supply or equip oneself with weaponry.

2. To prepare oneself for warfare or conflict.

v.tr.

1. To equip with weapons: armed themselves with loaded pistols; arm a missile with a warhead; arm a nation for war.

2. To equip with what is needed for effective action: tax advisers who were armed with the latest forms.

3. To provide with something that strengthens or protects: a space reentry vehicle that was armed with a ceramic shield.

4. To prepare (a weapon or electronic system, such as an alarm) for use or operation, as by releasing a safety device.

Idiom:

up in arms

Extremely upset; indignant.

[From Middle English armes, weapons, from Old French, pl. of arme, weapon, from Latin arma, weapons; see ar- in the Appendix of Indo-European roots. Verb, Middle English armen, from Old French armer, from Latin armāre, from arma.]

armed (ärmd) adj.

armer n.

Arm.

abbr.

1. Armenia

2. Armenian

ARM

abbr.

adjustable-rate mortgage

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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