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