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- break a link/tie/connection
- break a record
- break a strike
- break a sweat
- break-a-sweat
- break a tie
- break away
- breakaway
- breakaway group
- breakaway group/party/movement
- breakaway movement
- breakaway party
- breakaways
- breakbeat
- breakbeats
- break concentration
- breakdance
- breakdancer
- breakdancing
- break down
- breakdown
- breakdown lorry
- breakdown-lorry
- breakdownlorry
- breakdowns