Gwrthben, n. counter head: rivet
Gwrthblaid, n. adverse party
Gwrthblyg, n. duplicate
Gwrthbrawf, n. refutation
Gwrthbryn, n. counter buying
Gwrthbwys, n. counterpoise
Gwrthbwyth, n. retaliation
Gwrthchwyth, n. counter blast
Gwrthdafl, n. counter throw
Gwrthdaith, n. counter march