(historical) A member of La Montagne (The Mountain), a French political group active 1792-1799 during the French Revolution of 1789.

(biology, game theory) A model for the evolution and maintenance of informative communication between relatives, developed to explain begging behaviour in chicks.

(biology) pertaining to, or formed by, a zymogene / (biology) capable of producing a definite zymogen or ferment

(rare) Exceptionally unbelievable; of extreme unbelievability or unbelievableness.