Catchphrase (6)
'catchphrase' is the definition.
(eg a political catchphrase)
This is the entire clue.
(Other definitions for slogan that I've seen before include "Memorable advertising phrase" , "Catchy phrase in advertisement etc" , "War cry - advertising jingle" , "Advertising catchphrase" , "Identifying catchword" .)
(Other definitions for mantra that I've seen before include "Vedic hymn; slogan frequently repeated" , "Words repeated as an aid to meditation" , "Something said to focus concentration" , "Sacred words used as incantation" , "Word repeated as aid to concentration during meditation" .)
'catchphrase' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tag line that I've seen before include "Something memorable one might say" , "Catchphrase (mainly US)" , "Slogan" , "End of joke" .)