sin ‧ ew /ˈsɪnjuː/ BrE AmE noun [uncountable and countable]
[ Language: Old English ; Origin: seono ]
1 . a part of your body that connects a muscle to a bone:
The sinews on his neck stood out like knotted string.
2 . the sinews of something literary something that gives strength or support to a government, country, or system:
They have begun building the sinews of an independent nation.