Trustworthy, staunch (8)
I believe the answer is:
reliable
This clue is a double definition.
'trustworthy' is the first definition.
(synonyms)
'staunch' is the second definition.
(thesaurus)
(Other definitions for reliable that I've seen before include "Dependable, trustworthy" , "Trusty" , "Can be depended upon, trustworthy" , "Able to be depended on" , "Trustworthy - genuine" .)