Consideration, however, close to redundant (7)
I believe the answer is:
thought
'consideration' is the definition.
(thesaurus)
'however close to redundant' is the wordplay.
'however' becomes 'though' ('though' can be a synonym of 'however').
'close to' suggests the final letters (the close/ending of).
The last letter of 'redundant' is 't'.
'though'+'t'='THOUGHT'
(Other definitions for thought that I've seen before include "Idea, opinion" , "Reflection" , "Thinking process" , "Musing" , "Considered, believed" .)