Progenitor (6)
'progenitor' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sire that I've seen before include "Rise for male parent (4)." , "Generator" , "Ancestor" , "Bear" , "Old form of address to king - rise to it" .)
'progenitor' is the definition.
(parent is a kind of progenitor)
This is the entire clue.
(Other definitions for parent that I've seen before include "The company of which others are subsidiaries" , "Trepan for progenitor" , "Pa or Ma" , "person responsible for children" , "Immediate ancestor" .)