Stop talking (4,2)
'stop talking' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for clam up that I've seen before include "Refuse to talk like large shellfish?" , "Abruptly stop talking (colloq.)" , "Stop giving out" , "'Fall silent and refuse to talk (4,2)'" , "Keep mum" .)
'stop talking' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for pipe down that I've seen before include "make less noise" , "Stop talking" , "Shut up!" , "Be quiet!" , "Say no more!" .)
(Other definitions for hush that I've seen before include "Make or become silent or quiet" , "Soothe" , "Mum's the word" , "Make (someone) quiet" , "Noiselessness" .)
'stop talking' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for put a sock in it that I've seen before include "Keep mum" , "Quiten down" , "Stop endless yacking" , "Shut up!; tuition packs (anag.) (3,1,4,2,2)" , "Stop talking (3,1,4,2,2)" .)