What is Tray ?
Tray is (noun) 1. a flat board for carrying food, and things like glasses, cups and saucers He had his lunch on a tray in his bedroom. She bumped into a waitress who was carrying a tray of glasses. 2. a flat open container on a desk for documents which have to be dealt with There was a pile of letters in my tray when I returned to work.
source: Easier English, Student Dictionary Upper Intermediate Level