10 Welsh Words Now In The OED

1. Calennig, n. A New Year's gift. Also: the practice or custom observed on the morning of New Year's Day, usually by children, of going from door to door making a request (traditionally in the form of a song) for food, money, or other gifts
2. cawl, n.2 Soup
3. iechyd da, int. Cheers (lit good health)
4. mamgu, n. Grandmother (South Wales)
5. Senedd, n. (The Welsh) Parliament
6. sglods, n. Chips
7. tadcu, n. Grandfather (South Wales)
8. taid, n. Grandfather (North Wales)
9. twp, adj. (and n.) Stupid
10. ych a fi, int. Expressing disgust or disdain