Slogan of TV comedy originally ignored, then taken up (5)
I believe the answer is:
motto
'slogan' is the definition.
(synonyms)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for motto that I've seen before include "Recurring musical phrase" , "Phrase to express character" , "Message in cracker" , "Brief guiding rule" , "Shibboleth" .)