Sinewy means lean and strong, with the muscles showing. A sinewy arm, sinewy and tough, sinewy meat.
Of a person it is admiring: strength without bulk. Of meat it is a complaint, because sinew is connective tissue and does not soften quickly — long slow cooking is the answer. Note sinew, which means a tendon; and that the word is Old English.
1adjectivesinewyLean and strong, with the muscles showing.
“The old farmer had sinewy arms from a lifetime of hard work.”
sinewy is a quality of lean strength.
Middle English synwy is sinew plus -y. Sinew comes from Old English sinu, a tendon.
Middle English
synwy
English, today
sinewy
Built from
Middle English synwy, synewy, synowy (“tendonous”); equivalent to sinew + y.
Etymology from Wiktionary, CC BY-SA