noun Date: 1854 an academic cap consisting of a closely fitting headpiece with a broad flat projecting square top, 2. hawk 2, a board or platform about three feet (one meter) square for holding mortar
MORTARBOARD
Meaning of MORTARBOARD in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012