Subjoin \Sub*join"\, v. t. [imp. & p. p. {Subjoined}; p. pr. & vb. n. {Subjoining}.] [Cf. OF. subjoindre, L. subjungere. See {Sub-}, and {Join}, and cf. {Subjective}.] To add after something else has been said or written; to ANNEX; as, to subjoin an argument or reason. [1913 Webster] Syn: To add; annex; join; unite. [1913 Webster]