mum has definitions from the field of botany
1
[ adjective ] failing to speak or communicate etc when expected to

Synonyms

silent

Examples

"the witness remained silent"

Used in print

(Marvin Schiller, "The Sheep's in the Meadow,"...)

I went and , mum and nervous , all_but made a fool of myself .

Related terms

uncommunicative

2
[ noun ] informal terms for a mother

Related terms

mother

3
4
[ noun ] secrecy

Examples

"mum's the word"

Related terms

secrecy

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