Difficulty, poser (7)
I believe the answer is:
problem
I believe this is a double definition.
'difficulty' is the first definition.
(I know that problem is a type of difficulty)
'poser' is the second definition.
(I've seen this before)
(Other definitions for problem that I've seen before include "Puzzle - difficulty" , "Difficulty (these days, of any kind)" , "Matter hard to cope with" , "Something to be solved" , "Snag" .)