Stupid honour essentially elitist American wears (6)
I believe the answer is:
obtuse
'stupid' is the definition.
(similar in meaning)
'honour essentially elitist american wears' is the wordplay.
'honour' becomes 'OBE' (Order of the British Empire award).
'essentially' means to look at the middle letters.
'american' becomes 'us' (abbreviation for United States).
'wears' is an insertion indicator.
The central letter of 'elitist' is 't'.
't'+'us'='tus'
'obe' going around 'tus' is 'OBTUSE'.
(Other definitions for obtuse that I've seen before include "A stupid angle?" , "Dopey" , "Dim-witted" , "Blunt or unintelligent" , "'Dense, slow (6)'" .)