arm

English has two words spelled arm: the limb, inherited from Old English, and the weapon, from Latin arma through French; they had very different routes into English, though both probably go back to the same Indo-European root.^[1][2]

Pronunciation

• IPA: UK /ɑːm/, US /ɑːrm/^[3]

arm¹ limb

Etymology

The limb is inherited from Middle English arm,^[2][4] inherited from Old English earm,^[2][5] from Proto-Germanic *armaz,^[2][5][6] which is also the source of Old Saxon, Dutch and German arm, Old Frisian erm, Old Norse armr and Gothic arms.^[2][5][6] It is from Proto-Indo-European *ar- (“to fit together”),^[2][5] the root also of Latin armus “shoulder (of an animal)”, Greek harmós “joint”, Sanskrit īrmá- “arm” and Armenian armukn “elbow”.^[5][4]

Earliest recorded meaning

The upper limb of the human body: about 725, in Beowulf,^[5] and in the OED from about 950.^[7] The figurative sense “might, power, authority”, as in the secular arm, is equally old.^[7] An arm of the sea was already Old English.^[2]

Semantic evolution

A support or prop, right arm as one's main stay, is from 1382.^[7] Arm in arm is from about 1374, found in Chaucer,^[7][2] and at arm's length from 1580.^[7] Arm as a measure of length is from 1572.^[7] The verb “to give one's arm to” is from about 1612.^[7] The long arm of the law is from the mid-18th century,^[1] and arm-wrestling and arm-twister are from 1899 and 1915.^[2] To cost an arm and a leg seems to be from the 20th century.^[1]

Timeline

• c. 725 – the limb, in Beowulf.^[5]
• c. 950 – power, authority.^[7]
• c. 1374 – arm in arm.^[7]
• 1382 – a support.^[7]
• 1580 – at arm's length.^[7]
• mid-18th century – long arm of the law.^[1]
• 1899 – arm-wrestling.^[2]

Modern meaning

Noun

1. An upper limb of the human body, from the shoulder to the hand.
2. A similar part, such as the forelimb of an animal or a long part of a machine.
3. A part made to cover or support the arm, such as a sleeve or the side of a chair.
4. A narrow projection from a larger body: an arm of the sea.
5. A branch or division of an organisation.
6. Power or authority: the arm of the law.

Word family

• armful
• armless
• armpit
• armchair
• armband
• forearm

arm² weapon

Etymology

The weapon is inherited from Middle English armes (“weapons”), plural,^[2][4] borrowed from Old French armes (“arms, weapons; war, warfare”),^[2][6] from Latin arma (“weapons, tools”), a plural with no singular,^[2][6] from Proto-Indo-European *ar(ə)mo-, a suffixed form of Proto-Indo-European *ar- (“to fit together”), perhaps as “that which is fitted together”.^[2] The singular is a back-formation from the plural.^[4] The verb is inherited from Middle English armen, from Old French armer or directly from Latin armāre (“to furnish with arms”).^[2][6][4]

Earliest recorded meaning

Weapons: before 1250, in The Proverbs of Alfred,^[5] and in the OED before 1300.^[7] Etymonline dates armes, “weapons of a warrior”, to about 1300.^[2] The verb, to furnish with weapons, is from about 1200.^[2]

Semantic evolution

Defensive covering, armour, is from 1340.^[7] The heraldic sense, as in coat of arms, is from the early 14th century, after Old French usage;^[2] the arms were first borne on the shields of armed knights.^[2] A particular kind of weapon, in the singular, is from 1861.^[7] A branch of military service is from 1798, and a branch of any organisation by 1952.^[2] To bear arms, to do military service, is from the 1640s, and figurative up in arms from 1704.^[2] To prepare a weapon for use, as by releasing a safety device, is a modern sense.^[8]

Timeline

• c. 1200 – verb, to arm.^[2]
• before 1250 – weapons.^[5]
• early 14th century – heraldic arms.^[2]
• 1340 – armour.^[7]
• 1640s – to bear arms.^[2]
• 1704 – up in arms.^[2]
• 1798 – a branch of the armed forces.^[2]

Modern meaning

Noun

1. A weapon, especially a firearm.
2. A branch of a military force.
3. arms: warfare or military service.
4. arms: the heraldic bearings of a family, state or organisation; a coat of arms.

Verb

1. To supply with weapons; to prepare for war.
2. To equip with what is needed: armed with the facts.
3. To make a weapon or bomb ready to fire or explode.

Word family

• armed
• armer
• unarmed
• rearm
• disarm
• firearm
• sidearm

Related words

• army
• armour
• armada
• armadillo
• armistice
• armature
• harmony
• art

References

1. ^ a b c d Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
4. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c d e f g h i Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
6. ^ a b c d e Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
7. ^ a b c d e f g h i j k l m n o Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
8. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin