heterologous, a. [Hetero- + Gr. proportion.].
Characterized by heterology; consisting of different elements, or of like elements in different proportions; different; -- opposed to homologous; as, heterologous organs. [1913 Webster]
Heterologous stimulus. (Physiol.) See under Stimulus. -- Heterologous tumor (Med.), a tumor differing in structure from the normal tissues of the body.