unmentioned
adjective
uk/ˌʌnˈmen.ʃənd/us/ˌʌnˈmen.ʃənd/not referred to orspokenabout:
There is anotherissuethat cannotgounmentioned and that I mustraisenow.
Despite the government'spromisetoaddresstheissueofchildpoverty, thesubjectwasalmostcompletelyunmentioned in thebudget.
- Thereasonfortheirvisitwasleftunmentioned, and after a while everyonefelttooembarrassedtoask.
 - I wassurprisedto beintroducedto apreviouslyunmentionedyoungersisterof myboyfriend.
 - Theupsettingeventsfrom 40yearsago had gone unmentionedeversince.
 
Falling silent and not speaking
- be (on) non-speakersidiom
 - bite
 - bitesomethingback
 - button your lipidiom
 - clam
 - clam up
 - draw
 - gob
 - have nothing to say foryourselfidiom
 - mouth
 - silence is goldenidiom
 - speak
 - speechless
 - speechlessly
 - speechlessness
 - stick
 - stick insomeone'sthroatidiom
 - tongue-tied
 - unavowed
 - wordless