Definition of green monkey
: a long-tailed monkey of any of several African subspecies of a guenon (Cercopithecus aethiops syn. Chloroebus aethiops) having greenish-appearing hair and often used in medical research —called also vervet
Medical Definition of green monkey
: a long-tailed African monkey of the genus Cercopithecus (C. aethiops) that has greenish-appearing hair and is often used in medical research—called also vervet monkey
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