• Any one of several species of flatfishes of the genus Solea and allied genera of the family Soleidae, especially the common European species (Solea vulgaris), which is a valuable food fish. • Any one of several American flounders somewhat resembling the true sole in form or quality, as the California sole (Lepidopsetta bilineata), the long-finned sole (Glyptocephalus zachirus), and other species. • The bottom of the foot; hence, also, rarely, the foot itself. • The bottom of a shoe or boot, or the piece of leather which constitutes the bottom. • The bottom or lower part of anything, or that on which anything rests in standing. • The bottom of the body of a plow; -- called also slade; also, the bottom of a furrow. • The horny substance under a horse's foot, which protects the more tender parts. • The bottom of an embrasure. • A piece of timber attached to the lower part of the rudder, to make it even with the false keel. • The seat or bottom of a mine; -- applied to horizontal veins or lodes. • To furnish with a sole; as, to sole a shoe. • Being or acting without another; single; individual; only. • Single; unmarried; as, a feme sole.