IPA: /ˈtreɪfəl/
KK: /treɪfəl/
The amount of something that can fit in a tray.
She brought a trayful of cookies to the party.
Trayful → It is formed from "tray" (from Old French *traye*, meaning a shallow container) and "-ful" (meaning full of). The word "trayful" means full of trays or containing a tray's worth of items.
Think of a 'tray' as a shallow container that holds items, and '-ful' means full of — so a trayful is something that is full of items from a tray.