adjective
mum
MUM/mʌm/
Silent or unwilling to speak.
She keeps mum about the surprise.
Etymology
The earlier mum represented a closed-mouth sound, probably imitative, indicating unwillingness or inability to speak. That association with keeping the mouth shut produced the meaning “silent.”
In context
or keep mum and let his people wonder why they were suddenly at war with their neighbor.
we've got to keep mum. … We can't say at the moment.
More examples
- He remained mum during the questions.
- They stayed mum until the announcement.
- The witness was mum on that point.
Forms
mum
Similar words
- silent
- Not speaking or making sound.
- tight-lipped
- Unwilling to reveal information.