also: うでづく
noun, noun which may take the genitive case particle 'no'
main force; brute force; strong-arm
Refers to relying on physical strength or coercion rather than reason or negotiation. Often used in phrases like 腕ずくで (by force).
彼は腕ずくで相手を押さえつけた。
He pinned down his opponent by brute force.
交渉が決裂し、腕ずくに訴えるしかなかった。
Negotiations broke down, and they had no choice but to resort to force.
Irregular okurigana usage; can also be read as うでづく.
力ずく also means 'by force', but emphasizes physical power more generally, while 腕ずく specifically implies using one's arms or physical might in a coercive way.
Compound of 腕 (うで, 'arm') + ずく (a suffix meaning 'relying on' or 'by means of'). The suffix ずく is related to 尽く (つく, 'to exhaust'), implying using one's arms to the fullest.