- (Britain) Large girls' underpants traditionally worn as shorts during school sports activities.
1989, Roald Dahl, Matilda:
- "But instead of going there, I sneaked into the Trunchbull's room. And after a speedy search I found the drawer where she kept all her gym knickers."
- 1993, Angela Lambert, The Independent, 11 Oct 1993:
- I never knew why they singled me out, though at the time I believed it was because my mother made me wear green gym knickers and everyone else's were navy or white.
- 2010, Gail Emms, The Guardian, 5 Dec 2010:
- I remember being forced to do cross-country runs in horrible navy gym knickers, which is a nightmare when you're not exactly built like Paula Radcliffe [...].