I. crim ‧ son 1 /ˈkrɪmz ə n/ BrE AmE adjective
1 . deep red in colour:
The leaves turn crimson in autumn.
a crimson dress
2 . if you go crimson, your face becomes red because you are very angry or embarrassed
go/turn/flush/blush crimson
The boy blushed crimson.
crimson with
Her face was crimson with embarrassment.
—crimson noun [uncountable]
II. crimson 2 BrE AmE verb [intransitive] literary
if your face crimsons, it becomes red because you are embarrassed SYN blush :
Rachel crimsoned and sat down.