Everyone (3)
'everyone' is the definition.
(all people)
This is the entire clue.
(Other definitions for all that I've seen before include "in toto" , "'... things come to those who wait'" , "Monopolist controls this" , "without exception" , "Entire" .)
(Other definitions for isnt that I've seen before include "When abridged, has none of the quality of" , "In the present, not to be" , "Ain't" , "Is not (colloq.)" , "Is not (abbrev.)" .)