nutgalls
/ˈnʌtˌɡɔlz/
noun
- Plural of nutgall; hard, round growths on oak trees or other plants, often caused by insects, used historically for ink and dye.
- Nutgalls can be found on oak branches in late summer.
- The museum displayed a jar of nutgalls used in traditional dye-making.
- The old recipe called for crushed nutgalls to make the ink.