Fat-reduced sumo wrestling celebrated (6)
I believe the answer is:
famous
'celebrated' is the definition.
(I know that celebrated can be written as famous)
'fat-reduced sumo wrestling' is the wordplay.
'reduced' means to remove the last letter.
'wrestling' is an anagram indicator.
'fat' with its last letter taken off is 'fa'.
'sumo' anagrammed gives 'mous'.
'fa'+'mous'='FAMOUS'
(Other definitions for famous that I've seen before include "Well known" , "Well-known" , "Acclaimed" , "Renowned, noted" , "Eminent" .)