The Collaborative International Dictionary of English v.0.48:

Leucoline \Leu"co*line\ (l[=u]"k[-o]*l[i^]n or -l[=e]n), n.
   [Leuc- + L. oleum oil.] (Chem.)
   A nitrogenous organic base from coal tar, and identical with
   quinoline. Cf. Quinoline.
   [1913 Webster]