Alias intro (3)
I believe the answer is:
aka
'alias intro' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for aka that I've seen before include "Notation indicating alias or other name" , "Notation with initials indicating alternative name" , "Notation indicating alternative identity" , "Also known as, initially" , "Also called (abbrev.)" .)