Offering strange bait swallowed by cat (8)
I believe the answer is:
libation
'offering' is the definition.
(I've seen this before)
'strange bait swallowed by cat' is the wordplay.
'strange' indicates anagramming the letters.
'swallowed by' means one lot of letters goes inside another.
'cat' becomes 'lion' (lion is a kind of cat).
'bait' is an anagram of 'ibat'.
'ibat' inserted inside 'lion' is 'LIBATION'.
(Other definitions for libation that I've seen before include "Drink-offering" , "Liquid offering" , "A serving of an alcoholic beverage" , "Drink poured as offering to the gods" , "Drink poured out as offering to God" .)