Zealous eBay offer after camera came out (5)
I believe the answer is:
rabid
'zealous' is the definition.
(I've seen this before)
'ebay offer after camera came out' is the wordplay.
'ebay offer' becomes 'bid' (I've seen this in another clue).
'after' says to put letters next to each other.
'out' suggests deleting specific letters.
'camera' with 'came' removed is 'ra'.
'bid' put after 'ra' is 'RABID'.
(Other definitions for rabid that I've seen before include "Mad like deranged dog" , "Fanatical, infected" , "extremist" , "Affected by hydrophobia" , "Ill from a mad dog bite?" .)