Forthright Open University man accepting special post (9)
I believe the answer is:
outspoken
'forthright' is the definition.
(I know that forthright can be written as outspoken)
'open university man accepting special post' is the wordplay.
'open university' becomes 'OU'.
'man' becomes 'ken' (short for Kenneth).
'accepting' means one lot of letters goes inside another (inserted letters are accepted).
'special' indicates an anagram.
'ou'+'ken'='ouken'
'post' anagrammed gives 'tspo'.
'ouken' going around 'tspo' is 'OUTSPOKEN'.
(Other definitions for outspoken that I've seen before include "Inclined to say exactly what one thinks" , "Candid" , "Bold in speech" , "not reserved?" , "bluff" .)