antiveninPronunciation: /ˌantɪˈvɛnɪn/ (also antivenene /ˌantɪvɪˈniːn/)Definition of antivenin noun an antiserum containing antibodies against specific poisons, especially those in the venom of snakes, spiders, and scorpions. Derivatives antivenomPronunciation: /-ˈvɛnəm/ noun Origin: late 19th century: from anti- + ven(om) + -in1antivenin in other Oxford dictionaries Definition of antivenin in the US English dictionary