Do course designed in good taste (8)
I believe the answer is:
decorous
'in good taste' is the definition.
(similar in meaning)
'do course designed' is the wordplay.
'designed' indicates anagramming the letters (designed with the letters).
'do'+'course'='docourse'
'docourse' anagrammed gives 'DECOROUS'.
(Other definitions for decorous that I've seen before include "Appropriate" , "In good taste" , "Do course on being polite and well-behaved" , "Seemly" , "following the proper procedure" .)