stum [st?m]

keep stum

To remain silent; to not say anything; to avoid revealing secret or sensitive information. An alternative spelling of the more common "keep schtum/shtum." It's better to just keep stum when the boss starts flinging accusations than risk further incensing him. We'll need to keep stum about this deal for the time being.
See also: keep, stum
Farlex Dictionary of Idioms.

stum [st?m]

verb
See stumbles
See also: stum
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • keep stum
  • stum
  • enquire
  • enquire about (someone or something)
  • any fule kno
  • bollix
  • bollix up
  • bollixed up
  • geesh
  • Geesh!