no-no 
noun (plural no-nos) informal
A thing that is not possible or acceptable: perming highlighted hair used to be a definite no-no, but it’s now possible...
- So an office at that end of the building is a definite no-no as the droning hum could drive me mad.
- That sort of event was a definite no-no and he worked hard to prevent such things.
- Wiggling out was a definite no-no since he had already made sure that I had nowhere else to turn to.
Rhymes
- preside
- presidency
- president
- presidente
- president-elect
- presidentess
- president-for-life
- President General
- presidentiable
- presidential
- presidentialism
- presidentialist
- presidentially
- Presidential Medal of Freedom
- Presidential Range
- presidential year
- presidentiary
- president pro tem
- president pro tempore
- presidentress
- cotton gin
- cotton grass
- cotton lavender
- cotton-leaf worm
- cottonmouth