utter

Related to utter: utterly

not utter a word

To be completely silent; to remain discreet (about something); to not tell anyone (about something). All the while our father was shouting at us, my sister and I didn't utter a word. Tom, don't you dare utter a word about this! I would die of embarrassment if anyone were to find out.
See also: not, utter, word
Farlex Dictionary of Idioms.

not open one's mouth

 and not utter a word
Fig. not to say anything at all; not to tell something (to anyone). Don't worry, I'll keep your secret. I won't even open my mouth. Have no fear. I won't utter a word.
See also: mouth, not, open
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

not open one's mouth

Also, shut one's mouth; not say or utter a word . Be silent, repress one's feelings or opinions, keep a secret. For example, Don't worry, I'm not going to open my mouth on this issue, or She promised not to say a word about it to anyone. Also see hold one's tongue; keep one's mouth shut.
See also: mouth, not, open

utter a word

see under not open one's mouth.
See also: utter, word
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • not utter a word
  • utter a word
  • open your mouth
  • not open (one's) mouth
  • not open mouth
  • not open one's mouth
  • squeak out
  • dumpster fire
  • give out with (something)
  • give out with something
References in classic literature
"This reading had puzzled me extremely at first, but by degrees I discovered that he uttered many of the same sounds when he read as when he talked.
Frankenstein
He rose again to the surface, struggled with the last desperate effort of a drowning man, uttered a third cry, and felt himself sinking, as if the fatal cannon shot were again tied to his feet.
Dantes was so exhausted that the exclamation of joy he uttered was mistaken for a sigh.
Count of Monte Cristo
It was uttered impassively, as the bird sings his note.
When the colonel showed her the lump of sugar, holding it between the thumb and forefinger of his right hand, she again uttered her little wild cry, and sprang toward him; then she stopped, struggling against the instinctive fear he caused her; she looked at the sugar and turned away her head alternately, precisely like a dog whose master forbids him to touch his food until he has said a letter of the alphabet which he slowly repeats.
Adieu
The words were barely uttered, when he encountered a savage of gigantic stature, of the fiercest mien.
The two latter uttered their usual expressive exclamation, "hugh!" as the truth first glanced upon their minds, while the former, after a short, musing pause, took upon himself to reply.
Last of The Mohicans
As she uttered these words, and indicated, with her hand, the direction in which she wished them to proceed, the countryman looked round, and roughly asking what they took up the whole pavement for, passed on.
These words appeared to be addressed to the young lady, and were perhaps uttered with the view of afffording Nancy time to recover herself.
The young lady uttered a cry of surprise, and for a few moments they were so still that the listener could distinctly hear them breathe.
Oliver Twist Or The Parish Boys Progress
Then he recollected that this idea, which he had heard from an acquaintance and uttered as his own, came from a fable of Krilov's, and that the acquaintance had picked it up from a newspaper article.
Anna Karenina
Incapable of mastering his emotion, he arose, and tearing himself violently from the chamber where he had just found dead him to whom he came to report the news of the death of Porthos, he uttered sobs so heart-rending that the servants, who seemed only to wait for an explosion of grief, answered to it by their lugubrious clamors, and the dogs of the late comte by their lamentable howlings.
The Man in the Iron Mask
A UNION yesterday voiced "utter dismay" at the slashing of a quarter of the workers at an oil terminal.
Oil firm to axe 80 jobs at terminal
Alan Utter has been named provost and executive vice chancellor for academic affairs at Arkansas State University in Jonesboro, effective July 1.
Education