English teacher suspicious in absence of head’s representative (8)
I believe the answer is:
emissary
'representative' is the definition.
(I know that emissary is a type of representative)
'english teacher suspicious in absence of head's' is the wordplay.
'english' becomes 'e' (abbreviation).
'teacher' becomes 'miss' (I've seen this before).
'suspicious' becomes 'wary' (I've seen this before).
'in absence of head' means to remove the first letter.
'wary' with its initial letter taken away is 'ary'.
'e'+'miss'+'ary'='EMISSARY'
(Other definitions for emissary that I've seen before include "One sent" , "Government messenger" , "Diplomatic messenger" , "Person sent on a diplomatic mission" , "Agent possibly" .)