Trusting in later developments (7)
I believe the answer is:
reliant
'trusting' is the definition.
(synonyms)
'in later developments' is the wordplay.
'developments' indicates an anagram (I've seen 'development' mean this).
'in'+'later'='inlater'
'inlater' anagrammed gives 'RELIANT'.
(Other definitions for reliant that I've seen before include "Depending (on something)" , "Inspiring confidence" , "leaning" , "in need of assistance" , "Depending (upon)" .)