| any wasp of the family Cynipidae, the larvae of which form characteristic galls on plants. |
| gall wasp n. Any of various wasps of the family Cynipidae whose larvae produce distinctively shaped galls on oaks and other plants. |
gall wasp
any of a group of wasps in the family Cynipidae (order Hymenoptera) that are notable for their ability to stimulate the growth of galls (tissue swellings) on plants. Some gall wasp species are gall inquilines, meaning they do not cause the formation of galls but inhabit those made by other insects. The overgrowth of tissue, or gall, presumably is caused by a substance secreted by the immature insect living within it.
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