Live! Crazy life shows feeling! (6)
I believe the answer is:
belief
'feeling' is the definition.
(I know that feeling can be written as belief)
'live crazy life' is the wordplay.
'live' becomes 'be' (synonyms).
'crazy' indicates anagramming the letters.
'life' is an anagram of 'lief'.
'be'+'lief'='BELIEF'
'shows' is the link.
(Other definitions for belief that I've seen before include "Trust, faith (6)" , "Faith; confidence" , "Principle accepted without proof" , "Creed or opinion" , "Tenet, creed" .)