n. 1 (in full ichneumon wasp) any small hymenopterous insect of the family Ichneumonidae, depositing eggs in or on the larva of another insect as food for its own larva. 2 a mongoose of n. Africa, Herpestes ichneumon, noted for destroying crocodile eggs.
[ L f. Gk ikhneumon spider-hunting wasp f. ikhneuo trace f. ikhnos footstep ]