Definition of Mertensian in US English:

Mertensian

adjective

Zoology
  • Designating a proposed form of mimicry in which the model is a distasteful or moderately noxious animal and its mimic is a lethal or highly noxious one.

Origin

1960s; earliest use found in Robert D. Martin (b. 1942). From the name of Robert Mertens, German zoologist, who described such a pattern of mimicry in 1966 + -ian.