not breathe a word

verb (used without object), breathed [breethd] /briðd/, breath·ing.

1. to take air, oxygen, etc., into the lungs and expel it; inhale and exhale; respire.
2. (in speech) to control the outgoing breath in producing voice and speech sounds.
3. to pause, as for breath; take rest: How about giving me a chance to breathe?
4. to move gently or blow lightly, as air.
5. to live; exist: Hardly a man breathes who has not known great sorrow.
6. to be redolent of.
7. (of a material) to allow air and moisture to pass through easily: The jacket is comfortable because the fabric breathes.
8. (of the skin) to absorb oxygen and give off perspiration.
9. (of a wine) to be exposed to air after being uncorked, in order to develop flavor and bouquet.

verb (used with object), breathed [breethd] /briðd/, breath·ing.

10. to inhale and exhale in respiration.
11. to exhale: Dragons breathe fire.
12. to inject as if by breathing; infuse: She breathed life into the party.
13. to give utterance to; whisper.
14. to express; manifest.
15. to allow to rest or recover breath: to breathe a horse.
16. to deprive of breath; tire; exhaust.
17. to cause to pant; exercise.

Idioms

18. breathe down someone’s neck,
    1. to be close to someone in pursuit; menace; threaten: Police from four states were breathing down his neck.
    2. to watch someone closely so as to supervise or control: If everyone keeps breathing down my neck, how can I get my work done?
19. breathe freely, to have relief from anxiety, tension, or pressure: Now that the crisis was over, he could breathe freely.Also breathe easily, breathe easy.
20. breathe one’s last, to die: He breathed his last and was buried in the churchyard.
21. not breathe a word/syllable, to maintain secrecy; keep a matter confidential: I’ll tell you if you promise not to breathe a word.

verb

1. to take in oxygen from (the surrounding medium, esp air) and give out carbon dioxide; respire
2. (intr) to exist; be aliveevery animal that breathes on earth
3. (intr) to rest to regain breath, composure, etcstop your questions, and give me a chance to breathe
4. (intr) (esp of air) to blow lightlythe wind breathed through the trees
5. (intr) machinery
   1. to take in air, esp for combustionthe engine breathes through this air filter
   2. to equalize the pressure within a container, chamber, etc, with atmospheric pressurethe crankcase breathes through this duct
6. (tr) phonetics to articulate (a speech sound) without vibration of the vocal cordsCompare voice (def. 19)
7. to exhale or emitthe dragon breathed fire
8. (tr) to impart; instilto breathe confidence into the actors
9. (tr) to speak softly; whisperto breathe words of love
10. (tr) to permit to restto breathe a horse
11. (intr) (of a material) to allow air to pass through so that perspiration can evaporate
12. breathe again, breathe freely or breathe easily to feel reliefI could breathe again after passing the exam
13. breathe down someone’s neck to stay close to someone, esp to oversee what they are doingthe cops are breathing down my neck
14. breathe one’s last to die or be finished or defeated

v.c.1300, not in Old English, but it retains the original Old English vowel of its source word, breath. Related: Breathed; breathing. Not reveal a secret, keep concealed, as in You must promise not to breathe a word of what I’m about to tell you. This phrase relies on the verb breathe as meaning “to utter,” a usage dating from the late 1500s. In addition to the idioms beginning with breathe

breathe down someone’s neck

breathe easy

breathe life into

breathe one’s last

also see:

as I live and breathe

breathing space

not breathe a word