D defs.my
Entry 1 sense Webster, 1913

Mossback

· Moss·back · IPA /ˈmɔsˌbæk/
01 n. A veteran partisan; one who is so conservative in opinion that he may be likened to a stone or old tree covered with moss.
  1. 1.
    A veteran partisan; one who is so conservative in opinion that he may be likened to a stone or old tree covered with moss.[Political Slang, U.S.]