People scoffing a jinx? (7)
I believe the answer is:
mockers
This clue is a double definition.
'people scoffing' is the first definition.
(I know this)
'a jinx?' is the second definition.
(to put the mockers on something is to jinx it)
(Other definitions for mockers that I've seen before include "They jeer and deride" , "People scorning" , "put them on with disastrous effect" , "Satirists" .)