button one's lip
keep mum
keep one's lips sealed
tick a lock
silence
keep quiet
keep a low profile
hold one's peace
keep one's mouth shut
sing small
open one's big mouth
save one's breath to cool one's porridge
shush
close ranks
save one's breath
lie doggo
hushingly
keep shtum
put a sock in it
confidable
in hiding
doggo
guard one's tongue
out of sight
play dumb
between you and me
hush
quieten
zip one's lip
shushy
shut one's trap
shut one's face
shut one's mouth
quieting
hush-hush
shut one's gob
choops
mind one's language
husher
pipe down
dissemble
wheesh
tacit
clam up
shusher
put up or shut up
bite one's tongue
silence is violence
hush up
shushing
bite one's lip
blah blah blah
talkative
fall silent
hushfully
strike dumb
whist
feign
dummy up
keep to oneself
belt up
discreet
diam
shut up
quiet
evasive
close up
sulk
button up
fence
be quiet
mute
hushedness
aunt nell
listen in
hushable
voices off
natter
keep
discretion is the better part of valour
sit on the fence
exeleutherostomize
soap
declaim
unspeakingly
inveigh