"It is a big plate."
Translation:'S e truinnsear mòr a th' ann.
Yes. Apparently the Normans brought it over. Its original meaning was 'cutting [board]’ from a word related to English tranch(e) and trench. This is why it often refers specifically to a wooden plate in English.
I wonder if the same verb led to Gaelic trannsa 'aisle, corridor' which might have been a trench or 'cutting'?