Be abducted by one? (5)
I believe the answer is:
alien
'be' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'abducted by one?' is the wordplay.
'abducted' becomes 'lien' (I can't justify this - if you can you should believe this answer much more).
'by' means one lot of letters go next to another.
'one?' becomes 'a' (a thing is one thing).
'lien' put after 'a' is 'ALIEN'.
Can you help me to learn more?
(Other definitions for alien that I've seen before include "24a [ESTRANGE]" , "Clanger?" , "exciting film based in space" , "Foreign - film directed by Ridley Scott" , "Otherworldly" .)