Cake, something squelchy sent back (3)
I believe the answer is:
gob
'back' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for gob that I've seen before include "Clot of a slimy substance found in bog" , "A slangy mouth" , "Mouth (slang)" .)