柯林斯詞典in tray (also in-tray) (in trays) 1. N-COUNT An in tray is a shallow container used in offices to put letters and documents in before they are dealt with. Compare . (辦公室里存放待處理來函或來文的) 收文籃 (比較)(out tray)[英國英語] 返回 in-tray