Gwrthyni, n. deformity, ugliness

Gwrthwad, n. a counter denial

Gwrthwaith, n. a retroaction

Gwrthwal, n. a contramure

Gwrthwon, n. contravention

Gwrthwe, n. a lining

Gwrthwead, a counter weaving

Gwrthwediad, n. contradiction

Gwrthwedd, n. a contrast

Gwrthwenwyn, n. a counterpoison; an antidote