arm
Pluralarms
Pluralarms
- 1Either of the two upper limbs of the human body, from the shoulder to the wrist or hand; in anatomy, strictly the part from shoulder to elbow.
The nurse wrapped a bandage around his injured arm.
Swimmers use their arms to pull through the water.
UsageUsually with a possessive: I hurt my arm, but take someone by the arm. Note arm in arm and in her arms.
Note
In everyday speech the limb runs from shoulder to wrist and may take in the hand, but anatomists keep the word for the stretch from shoulder to elbow.
Checked 1 Nov 2026 · 1 fact
- Anatomically, the arm extends from shoulder to elbow. en.wikipedia.org
- 2To supply a person, group or force with weapons, or to take up weapons yourself, in readiness for fighting.
The government decided to arm the coast guard with heavier cannon.
Smugglers armed the fishing boats with hidden guns.
UsageMost often arm someone with something; armed also works as an adjective: armed police, armed with rifles.
Similarequip
Oppositedisarm
Note
Once said of armor as well as weapons, the verb now leans toward putting weapons in someone's hands. George R. R. Martin's A Dance with Dragons (2011) still mixes the two, when a row of snowmen on a castle wall is armed with spears and shields and topped with iron halfhelms.
Checked 3 Nov 2026 · 2 facts
- George R. R. Martin wrote A Dance with Dragons, first published in 2011. en.wikipedia.org
- The novel describes snowy sentinels arranged along an inner wall, equipped with spears, shields and iron halfhelms. en.wiktionary.org
- 3A weapon, especially one carried or used for fighting, attack, or self-defense.
For more than a century the rifle remained the basic arm of the foot soldier.
The treaty required both sides to surrender their arms.
UsageMostly plural: arms, as in the arms trade, arms control, lay down their arms.
Similarweapon
Note
The singular is the newcomer. English took the plural arms from Old French and Latin arma, "weapons," and later formed arm from it. That history explains why the plural still does most of the work: the right "to keep and bear Arms" in the Second Amendment of 1791, or Robert Louis Stevenson's narrator in Treasure Island feeling "well supplied with arms."
Checked 30 Oct 2026 · 5 facts
- The weapon noun arm was formed later from plural arms, borrowed through Old French from Latin arma, meaning weapons. en.wiktionary.org
- The Second Amendment dates to ratification in 1791. archives.gov
- The Second Amendment contains the words to keep and bear Arms. wwws.loc.gov
- Robert Louis Stevenson wrote Treasure Island. gutenberg.org
- The narrator in Treasure Island describes feeling well supplied with arms. gutenberg.org
- 4A long, narrow, fairly rigid part that extends out from the main body or center of an object, such as the side support of a chair or the reach of a crane.
She perched on the arm of the sofa and listened to the argument.
When the song ended, the record player's arm lifted and swung back to its rest.
- 5A distinct branch or division of a larger organization, responsible for part of its work.
The intelligence arm of the agency handles foreign operations.
The bank's investment arm reported strong profits this year.
UsageOften after a possessive or noun: the charity's research arm, the political arm of a movement.
- 6To provide someone with the knowledge, skills, authority, or tools needed for a particular task; to equip.
The training program armed new managers with practical leadership tools.
We must arm voters with accurate information before the election.
UsageArm someone or yourself with something: armed with the facts, arm yourself with patience.
Similarequip, provide, furnish, supply, prepare
Note
The figurative verb is far from new. The anonymous play The Life and Death of Jack Straw (1593) says an office "doth not arme thee with such authoritie," and the King James Bible of 1611 urges readers to "arm yourselves likewise with the same mind."
Checked 1 Nov 2026 · 5 facts
- The Life and Death of Jack Straw is an anonymous play. emed.folger.edu
- The play was first published in 1593. emed.folger.edu
- The play contains the quoted figurative use of arm concerning an office's authority; Jack Straw speaks the line. gutenberg.org
- The King James Bible was first published in 1611. wwwe.lib.cam.ac.uk
- The King James Bible urges readers to arm yourselves likewise with the same mind, in 1 Peter 4:1. en.wikisource.org
- 7Heraldic bearings or insignia: the symbols representing a family, institution, or state.
The city's arms, a gold lion on a blue shield, are carved above the door of the town hall.
Each banner bore the arms of a different noble house.
UsageMost often in coat of arms; on its own it takes a plural verb: the city's arms are.
- 8War; hostilities; or the deeds and exploits performed in war.
UsageLives on in set phrases: take up arms, a call to arms, feats of arms.
Note
Arms can name the fighting itself, not only its tools, and also the deeds done in war. Outside poetry and older prose, this sense now lives on mainly in set phrases such as a feat of arms or brothers in arms, where the word means warfare rather than weapons.
Checked 3 Nov 2026 · 2 facts
- Arms can mean warfare, hostilities, or deeds performed in war. en.wiktionary.org
- The expression brothers in arms refers to fellow combatants, with in arms meaning in combat or at war. en.wiktionary.org
Less common meanings
- 9To make a weapon, bomb, alarm or other system ready to go off or act; also, of such a system, to become ready in this way.
The crew was ordered not to arm the bombs until the plane was over the target.
Before going to bed, he armed the alarm system and checked that every window was locked.
UsageCommon with alarms and explosives: arm the alarm, arm a bomb; the opposite is disarm.
Oppositedisarm, deactivate
- 10The section of a garment that covers the arm; a sleeve.
The left arm of his old jacket was worn thin at the elbow.
One arm of the coat had a small tear near the cuff.
UsageSleeve is the everyday word; arm mostly comes as the arm of a coat or shirt.
Similarsleeve
Note
In Moby-Dick (1851), Herman Melville has one arm of a man's jacket streaming behind him "like the broidered arm of a huzzar's surcoat." J. G. Farrell's Troubles notes a stain under the arm of a silk dress, and in Zadie Smith's White Teeth a boy is caught by the arm of his shirt.
Checked 1 Nov 2026 · 5 facts
- Moby-Dick was first published in 1851. commons.wikimedia.org
- Herman Melville wrote Moby-Dick. en.wikisource.org
- The novel describes a jacket sleeve streaming behind a man using the quoted comparison. etc.usf.edu
- J. G. Farrell's Troubles describes a stain under the arm of a silk dress. en.wiktionary.org
- Zadie Smith's White Teeth describes a boy being caught by his shirt sleeve. en.wiktionary.org
- 11In baseball slang, a pitcher.
The team signed a hard-throwing arm to anchor the bullpen.
They need one more reliable arm before the playoffs start.
Note
Baseball names the player by the part that does the work. A club "needs another arm" or signs a reliable one, and arms are counted like assets on a roster. The word is slang of the clubhouse and the sports page. In formal writing, or for readers who do not follow the game, pitcher is the safer choice.
- 12A limb or grasping or moving organ belonging to an animal without a backbone.
Each arm of the squid is lined with rows of suckers.
When threatened, the brittle star can shed its arms and grow new ones.
Similarlimb
- 13Power or strength to act, and the support that power can give to others.
Exiled dissidents soon learned that the regime's arm could reach them even overseas.
She trusted the strong arm of justice to protect her.
UsageMostly in set phrases: the long arm of the law, the strong arm of the state.
Note
Power is pictured as something that reaches: the arm of the law, the secular arm, and in the King James Bible of 1611, "the arm of the Lord." Adjectives such as strong sharpen it, and the sense is of power that can stretch out and take hold.
Checked 1 Nov 2026 · 2 facts
- The King James Bible was first published in 1611. wwwe.lib.cam.ac.uk
- The King James Bible contains the phrase “the arm of the Lord” (Isaiah 53:1). en.wikisource.org
- 14A narrow stretch of sea, lake, or river extending inland from the main body of water.
The fishing village sat at the head of a sheltered arm of the bay.
Glacial melt feeds the long northern arm of the lake.
Note
Water is pictured here as a body with limbs: an arm reaches out from a lake or sea the way a limb leaves the torso. The larger water is often named with it (Shelburne Bay is an arm of Lake Champlain). The word therefore stresses a bay's place within a larger system, while inlet or bay puts more weight on its shape.
Checked 30 Oct 2026 · 3 facts
- There is no such naming rule; Lake Champlain, the example's larger body of water, was named after Samuel de Champlain. parks.canada.ca
- Shelburne Bay is an arm of Lake Champlain. en.wiktionary.org
- Bay and inlet also describe water features connected to a larger body of water; this relationship is not exclusive to arm. pubs.usgs.gov
- 15
- 16Either of the two parts into which a chromosome is divided.
The short arm of the chromosome carries fewer genes than the long one.
A mutation on the long arm caused the inherited disorder.
Note
Geneticists divide a chromosome at its centromere into two segments, and each segment is an arm. The shorter is labeled p and the longer q, so a gene's position is often stated by arm, as in a mutation on the long arm. Short arm and long arm are the standard collocations, and the letters let a location be written compactly.
Checked 30 Oct 2026 · 3 facts
- The centromere divides a chromosome into two sections called arms. genome.gov
- The short arm is labeled p and the long arm q. medlineplus.gov
- Chromosome arms are used in describing gene locations, and their letters enable compact location notation. medlineplus.gov
- 17To cover or fit something with a plate, or with anything that adds strength, force, security, or efficiency.
In the mid-1800s, navies began to arm wooden warships with thick iron plates to protect them from cannon fire.
To learn what the seabed was like, sailors armed the bottom of the sounding lead with tallow, which picked up sand or mud.
- 18To take someone by the arm, or to lift a person up in one's arms.
Arm your prize; / I know you will not lose him.
1613, John Fletcher, William Shak[e]speareAnd make him with our pikes and partisans / A grave: come, arm him.
1611, William Shakespeare, “The Tragedie of Cymbeline”Note
Shakespeare used this verb for holding someone, not for equipping them. In Cymbeline, "come, arm him" means lift the body in your arms. In John Fletcher and Shakespeare's The Two Noble Kinsmen, "Arm your prize" means much the same: hold her close. Modern readers easily hear the "supply with weapons" verb instead, but this one grew from the limb. It is obsolete now, a word to recognize rather than use.
Checked 30 Oct 2026 · 4 facts
- Shakespeare uses arm for lifting a body in Cymbeline; Lucius says the quoted words. folger.edu
- John Fletcher and Shakespeare wrote The Two Noble Kinsmen. folger.edu
- Theseus addresses Arcite; the prize is Emilia. Change 'him' to 'her'. folger.edu
- The holding verb derives from the limb sense. en.wiktionary.org
- 19To fit a magnet with an armature, a piece of soft iron placed across its poles.
- 20Having little money or few possessions; not wealthy.
- 21Pitiful or wretched; deserving to be pitied.
Showing meanings only.
Practice
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Origins
This sense comes from Middle English arm, from Old English earm, going back through Proto-West Germanic and Proto-Germanic *armaz ('arm') to a Proto-Indo-European root *h₂er- ('to join, fit together'). It is related to Dutch arm, German Arm, and the Scandinavian arm, as well as Latin armus ('shoulder') and Ancient Greek harmós ('joint, shoulder').
Checked 31 Oct 2026 · 5 facts
- Arm descends from Middle English arm and Old English earm through Proto-West Germanic and Proto-Germanic *armaz, meaning 'arm'. en.wiktionary.org
- The ultimate root is Proto-Indo-European *h₂er-, meaning 'to join, fit together'. en.wiktionary.org
- Dutch arm, German Arm, and Scandinavian arm are cognates. en.wiktionary.org
- Latin armus means 'shoulder' and is cognate with English arm. en.wiktionary.org
- Ancient Greek harmós means 'joint, shoulder' and is cognate with English arm. en.wiktionary.org
The noun was formed from arms, which came through Old French armes from Latin arma ('weapons'); the verb came separately through Old French armer from Latin armāre ('to arm'). Both go back to the root *h₂er- ('to fit together') behind the body-part arm.
Checked 31 Oct 2026 · 4 facts
- The weapons noun arm was formed from plural arms, through Old French armes from Latin arma, meaning weapons. en.wiktionary.org
- The verb entered separately through French armer from Latin armāre. gutenberg.org
- Latin armāre means to arm and derives from arma, giving the noun and verb a shared ultimate root. en.wiktionary.org
- The shared root *h₂er- means to fit together and also underlies the body-part noun arm. en.wiktionary.org