oak apple

noun

oak apple

noun

1

A spherical type of oak gall, produced by an oak gall wasp (tribe Cynipini).

[T]he small Apples which I have often observ'd to grow on the leaves of an Oak call'd Oak-apples […] are nothing but the Matrices of an Insect, as I elsewhere show.1665, Robert Hooke, Micrographia, section XXV:

Derived terms: Oak Apple Day

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.