0 shocking or embarrassing, and therefore not allowed or disapproved of as a subject of conversation:
the unmentionable possibility that we might lose the war
Both stories are constructed around shameful secrets and unmentionable activities.
Critics of sensation fiction argued that readers were bound to be negatively influenced by reflecting too long on subjects unmentionable in polite society.
Thirdly, we must consider the unmentionable—labour market policy.
I will not mention the unmentionable any more.
I wish to say a few words on a matter which seems to have been almost unmentionable in politics since 1944.
It has been placed on the list of things which are unmentionable.
When he might have mentioned the unmentionable, he was moved to other responsibilities.
It was unmentionable, not because it was morally degrading or wrong.
