mortarboard
Word family nounmortarmortarboard
College
mor·tar·board /ˈmɔːtəbɔːd $ ˈmɔːrtərbɔːrd/ noun [countableC] 
SECa black cap with a flat square top worn by members of some universities on formal occasions 学士帽，学位帽 →5 see picture at 见图 hat- playgrounds
- play group
- play-group
- playgroup
- play-groups
- playgroups
- play happy families
- play hardball
- play hard to get
- play hell with
- play hell with something
- play hell with sth
- play hooky
- playhouse
- playhouses
- playing
- playing-card
- playing card
- playingcard
- playing cards
- playing-cards
- playing-field
- playing field
- playingfield
- playing fields