Conjectures made by right-wingers entertaining ambassador (8)
I believe the answer is:
theories
'conjectures' is the definition.
(I've seen this before)
'right-wingers entertaining ambassador' is the wordplay.
'right-wingers' becomes 'tories' (Tory is an example).
'entertaining' indicates putting letters inside.
'ambassador' becomes 'he' (His or Her Excellency).
'tories' enclosing 'he' is 'THEORIES'.
'made by' acts as a link.
(Other definitions for theories that I've seen before include "Assumptions" , "Abstract principles" , "Ideas or suppositions" , "Hypotheses, possibilities" , "General principles or opinions" .)