Zealous group from bygone age recalled (5)
I believe the answer is:
eager
'zealous' is the definition.
(synonyms)
'group from bygone age recalled' is the wordplay.
'group' says the answer is hidden in the clue (I've seen 'group of' mean this (group of letters from the clue)).
'EAGER' can be found hidden inside 'from bygone age recalled'.
(Other definitions for eager that I've seen before include "Alert and active type?" , "hungry" , "Enthusiastic, agog" , "Showing keen interest" , "Enthusiastic, raring to go" .)