Wise man, naive in the shade (4,5)
I believe the answer is:
sage green
'the shade' is the definition.
(I've seen this before)
'wise man naive' is the wordplay.
'wise man' becomes 'sage' (sage is a kind of wise man).
'naive' becomes 'green' (similar in meaning).
'sage'+'green'='SAGE-GREEN'
'in' acts as a link.
(Other definitions for sage green that I've seen before include "Dull colour" , "Colour of plant" .)