Bitter \Bit"ter\, n. [See {Bitts}.] (Naut.) AA turn of the cable which is round the bitts. {Bitter end}, that part of a cable which is abaft the bitts, and so within board, when the ship rides at anchor.
bitter end n 1: the final extremity (however unpleasant it may be); "he was determined to fight to the bitter end" 2: (nautical) the inboard end of a line or cable especially the end that is wound around a bitt