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
- push plow
- push poll
- push-polling
- push present
- push process
- push processing
- push-pull
- throb
- throes
- Throgs Neck
- thrombectomy
- thrombi
- thrombin
- thrombo-
- thrombocyte
- thrombocythaemia
- thrombocytopenia
- thromboembolic
- thromboembolism
- thrombogenic
- thrombogenicity
- thrombolysis
- thrombolytic
- thrombophilia
- thrombophlebitis