Noun | 1. | family Ichneumonidae - ichneumon flies arthropod family - any of the arthropods Hymenoptera, order Hymenoptera - an order of insects including: bees; wasps; ants; ichneumons; sawflies; gall wasps; etc. ichneumon fly - hymenopterous insect that resembles a wasp and whose larvae are parasitic on caterpillars and other insect larvae |