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- overdosage
- overdose
- overdosed
- overdoses
- overdosing
- overdraft
- overdrafts
- overdrawn
- overdress
- overdressed
- overdresses
- overdrive
- overdrives
- overdue
- overdues
- overeat
- overeaten
- overeater
- overeaters
- overeating
- overeatings
- overeats
- overegg
- overegg the pudding
- overemphases
- 两头红
- 两好合一好
- 两好并一好
- 两姨
- 两姨亲
- 两审终审制
- 两小无猜
- 两尺半
- 两层皮
- 两岸
- 两岸三通
- 两广
- 两张皮
- 两弹一星
- 两当
- 两心
- 两性
- 两性人
- 两性关系
- 两性化合物
- 两性巢
- 两性物质
- 两性生殖
- 两性花
- 两手