Next in line (2,4)
'next in line?' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for heir that I've seen before include "Expected successor" , "Natural successor" , "Someone expected to inherit" , "One who inherits" , "One expected to succeed?" .)
'next in line' is the definition.
(I've seen this in another clue)
This is the entire clue.