arm 2 (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.
a. Warfare: a call to arms against the invaders.
b. Military service: several million volunteers under arms; the profession of arms.
a. Heraldry Bearings.
b. Insignia, as of a state, an official, a family, or an organization.
v. armed, arm·ing, arms
1. To supply or equip oneself with weaponry.
2. To prepare oneself for warfare or conflict.
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.
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.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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:
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.