SIN'EWY, adjective 1. Consisting of a sinew or nerve. The sinewy thread my brain lets fall. 2. Nervous; strong well braced with sinews; vigorous; firm; as the sinewy Ajax. The northern people are large, fair complexioned, strong, sinewy and courageous.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI