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
- cholerical
- cholerically
- cholericly
- choleric passion
- choleriform
- cholerine
- choleroid
- cholerous
- cholestasis
- cholestatic
- cholestearin
- cholestearine
- cholesteraemia
- cholesterate
- cholesteremia
- cholesteric
- cholesteride
- cholesterin
- cholesterine
- cholesterinic
- cholesterol
- cholesterol-conscious
- cholesterol count
- cholesterol-free
- cholesterol-laden