arm (zeroa`, 'ezroa`, dera`; brachion; chotsen, katheph): The usual form is zeroa` from the root zara`, "to spread." The arm may be "stretched out." 'Ezroa` is this form with prosthetic 'aleph (Job 31:22; Jer 32:21), and dera` is the Aramaic form. Chotsen is really "bosom," thus the Revised Version (British and American) (Isa 49:22); and katheph is "shoulder," thus the Revised Version (British and American) (Job 31:22). Compare cheir, also, in Ac 11:21.
⇒See a list of verses on ARM in the Bible.
Figurative: The arm denotes influence, power, means of support or conquest. The arms of Moab (Jer 48:25) and of Pharaoh (Eze 30:21 ff) are broken. The arm of Eli and the arm of his father's house are to be cut off (1Sa 2:31). Because the arm wielded the sword it signified "oppression" (Job 35:9). The arms are the means of support, therefore to refuse to aid the fatherless is to break their arms (Job 22:9).
Applied anthropomorphically to God, the arm denotes also His power, power to deliver, support, conquer. His "outstretched arm" delivered Israel from Egypt (Ex 6:6; De 4:34, etc.). They support: "Underneath are the everlasting arms" (De 33:27). His arm protects (Isa 40:11). Yahweh is sometimes likened to a warrior and smites with His arm (Ps 89:10; Isa 63:5; Jer 21:5). The arm of Yahweh is holy (Ps 98:1; Isa 52:10). Many other passages of Scripture might be quoted showing how the power of God to redeem, judge, protect, punish is expressed by the idea of "the arm of Yahweh."
⇒See the definition of arm in the KJV Dictionary
S. F. Hunter