Primary graduates in charge (5)
I believe the answer is:
basic
'primary' is the definition.
(thesaurus)
'graduates in charge' is the wordplay.
'graduates' becomes 'bas' (I've seen this in other clues).
'in charge' becomes 'ic'.
'bas'+'ic'='BASIC'
(Other definitions for basic that I've seen before include "Forming a foundation" , "Popular programming language" , "Staple; ordinary" , "Key" , "At the simplest level" .)