Plain, obvious (7)
I believe the answer is:
evident
I believe this is a double definition.
'plain' is the first definition.
(I know that plain can be written as evident)
'obvious' is the second definition.
(similar in meaning)
(Other definitions for evident that I've seen before include "Plain to see" , "Readily apparent" , "Visible - plain" , "Comprehensible - manifest" , "clearly visible" .)