beet

beet /ˈbiːt/ noun
plural beets
beet
/ˈbiːt/
noun
plural beets
Britannica Dictionary definition of BEET
[count]
1 
US
a  : a garden plant with thick leaves and a rounded red root
— called also (British) beetroot
b  : the rounded red root of the beet plant that is eaten as a vegetable
— called also (British) beetroot
— see color picture on this page
2 
British : sugar beet

beet red

or red as a beet
: red in the face especially from embarrassment