LY, a termination of adjectives, is a contraction of Sax.lie, G.lich, D.lyk, Dan.lige, Sw.lik, Eng.like; as in lovely, manly, that is, love-like, man-like. As the termination of names, ly signifies field or plain, Sax. leag, Eng. lay, lea or ley, Latin locus.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI