The Collaborative International Dictionary of English v.0.48:
Limner \Lim"ner\ (l[i^]m"n[~e]r), n. [F. enlumineur, LL. illuminator. See Limn, and cf. Alluminor.] A painter; an artist; esp.: (a) One who paints portraits. (b) One who illuminates books. [Archaic] [1913 Webster]WordNet (r) 3.0 (2006):
limner n 1: a painter or drawer of portraits [syn: portraitist, portrait painter, portrayer, limner]