keep (someone or something) back
idiomDefinition of keep (someone or something) back
1
: to not allow (someone) to go near something
The police kept the spectators back.
2
US
: to not allow (a student) to advance to the next grade level
—usually used as (be) kept back Students who fail the exam may be kept back a year.
3
British
: to require (a student) to stay at school after classes have ended
She was kept back for talking in class.
4
: to not allow (something) to appear or be known
He struggled to keep back his tears. The government kept back some crucial information from the media.