Shtum in the London Times

James Delingpole, who doesn't seem to be Jewish, has used a Yiddishism in a London Times (of all places) story today:

The first thing husbands very necessarily keep shtoom about is their nagging discomfort at having got married in the first place.

That's the British spelling, I guess, but by me it's

shtum

meaning, to keep quiet, be speechless, 'mum's the word'.

I'm shtum that he knows the word.