Webster's Revised Unabridged Dictionary · 1913

Sinew

Sinew , noun

[Old English sinewe, senewe, Anglo-Saxon sinu, seonu; akin to Dutch zenuw, Old High German senawa, German sehne, Icelandic sin, Swedish sena, Danish sene; compare Sanskrit snāva. r290.]

1.
(Anatomy) A tendon or tendonous tissue. See Tendon.
2.
Muscle; nerve. [Rare] — Sir J. Davies
3.
Figuratively: That which supplies strength or power.
The portion and sinew of her fortune, her marriage dowry. — Shakespeare
The bodies of men, munition, and money, may justly be called the sinews of war. — Sir W. Raleigh

Money alone is often called the sinews of war.

Sinew , transitive verb

To knit together, or make strong with, or as with, sinews. — Shakespeare
Wretches, now stuck up for long tortures... might, if properly treated, serve to sinew the state in time of danger. — Goldsmith