— unmentionableness , n.
/un men"sheuh neuh beuhl/ , adj.
1. not mentionable; inappropriate, unfit, or improper for mention, as in polite conversation; unspeakable.
n.
2. something that is not to be mentioned: That subject was classed among the unmentionables.
3. unmentionables ,
a. undergarments.
b. (formerly) trousers or breeches.
[ 1820-30; UN- 1 + MENTIONABLE ]