One likes to have people for dinner (8)
I believe the answer is:
cannibal
'dinner' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'one likes to have people' is the wordplay.
I cannot really understand how this works, but
'one' could be 'an' (an apple is one apple) and 'an' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'for' is the link.
Can you help me to learn more?
(Other definitions for cannibal that I've seen before include "One who eats its own species" , "Animal that eats it own kid (8)." , "One eating own species" , "Fellow consumer" , "One eats human flesh" .)