Standard places to eat last of Victoria sponges (9)
I believe the answer is:
parasites
'sponges' is the definition.
('parasite' can be a synonym of 'sponge')
'standard places to eat last of victoria' is the wordplay.
'standard' becomes 'par' (standard of play in golf).
'places' becomes 'sites' (a site is a place or location).
'to eat' means one lot of letters goes inside another.
'last of' suggests the final letters.
The last letter of 'victoria' is 'a'.
'par'+'sites'='parsites'
'parsites' enclosing 'a' is 'PARASITES'.
(Other definitions for parasites that I've seen before include "Passengers" , "They live off other organisms" , "they need indulgent hosts" , "Hangers-on" , "unwelcome guests" .)