Definition of biorational in English:

biorational

Pronunciation /ˌbʌɪə(ʊ)ˈraʃ(ə)n(ə)l/ /ˌbʌɪə(ʊ)ˈraʃən(ə)l/

adjective

Farming
  • Designating or relating to pest and weed control agents used because of their specific effects upon the organisms they are intended to control, rather than because of their toxicity or other general effects; employing or involving such agents.

Origin

1970s.