Rim \Rim\, n. [As. rima, reoma, edge; cf. W. rhim, rhimp, a rim, edge, boundary, termination, Armor, rim. Cf. {Rind}.] 1. The border, edge, or margin of a thing, usually of something circular or curving; as, the rim of a kettle or basin. [1913 Webster] 2. The lower part of the abdomen. [Obs.] --Shak. [1913 Webster] {Arch rim} (Phonetics), the line between the gums and the palate. {Rim-fire cartridge}. (Mil.) See under {Cartridge}. {Rim lock}. See under {Lock}. [1913 Webster]