n. An extension from the body of an aquatic animal, which serves for propelling, steering, or balancing in the water, and is developed from various parts of the body, generally as an alate or wing-like organ; a pinna.n. In sporting, a general term for fish, as in the phrase “fin, fur, and feather.”n. Something resembling a fin.n. A fin-like organ or attachment, or one appearing or used like a fin; in slang language, the hand.n. The sharp plate in the colter of a plow.n. In molding, a thin projection on the surface of a casting, caused by the imperfect approximation of two molding-boxes, containing each a part of the mold. The fin is formed by the metal running in between the two parting surfaces.n. In com., a blade of whalebone.n. A slip inserted longitudinally into a shaft or arbor, and left projecting so as to form a guide for an object which may slip upon it, but not rotate.n. A tongue on the edge of a board.n. See the adjectives, and def. 1.To carve or cut up, as a fish.To fin out: as, a finning whale.n. A Middle English form of fine.A Middle English form of fine.A dialectal variant of find.n. See Finn.n. The thin sheet of metal squeezed out between the collars of the rolls in a roll-train.n. An abbreviation of the Latin ad finem, at or to the end.n. An abbreviation of Finland;n. of Finnish.