Trend-setter in wild caper (5)
I believe the answer is:
pacer
'trend-setter' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'wild caper' is the wordplay.
'wild' is an anagram indicator.
'caper' is an anagram of 'PACER'.
'in' is the link.
Can you help me to learn more?
(Other definitions for pacer that I've seen before include "One setting race speed" , "setting the rate" , "Competitor" , "early race leader?" , "One walking steadily" .)