An insect gall on oak woods, caused by certain wasp larvae.
Oak gall.
a big, smooth, circular gall produced regarding the leaves regarding the American purple oak by a gallfly (Cynips confluens). It is green and pulpy when youthful.
An oak-gall. See gal.
In Australia, a cone of any one of many types of Casuarina, or she-oak, specifically C. stricta. The youthful cones and foliage have an acid flavor when chewed, and afford great relief in situations of thirst. See she-oak and Casuarina.
How would you define oak apple?