FOUL'LY, adverb 1. Filthily; nastily; hatefully; scandalously; disgracefully; shamefully. I foully wronged him; do, forgive me, do. 2. Unfairly; not honestly. Thou play'dst most foully for it.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI