Tell, advise (7)
I believe the answer is:
apprise
I believe this clue is a double definition.
'tell' is the first definition.
(I've seen this before)
'advise' is the second definition.
(I know that advise can be written as apprise)
(Other definitions for apprise that I've seen before include "Give notice" , "Formally inform, notify" , "Give information to" , "Inform, make aware of" , "Provide with information" .)