sinew
[noun]
Synonyms: power, arm, beef, energy, force, might, muscle, potency, strength, strong arm, mainstay, backbone, pillar

[TahlilGaran] English Synonym Dictionary ▲

sin‧ew /ˈsɪnjuː/ 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.

[TahlilGaran] Dictionary of Contemporary English ▲