Idealistic, dear? Yes? Try to be different (6-4)
I believe the answer is:
starry-eyed
'idealistic' is the definition.
(thesaurus)
'dear? yes? try to be different' is the wordplay.
'to be different' indicates an anagram (letters placed in a different order).
'dear'+'yes'+'try'='dearyestry'
'dearyestry' anagrammed gives 'STARRY-EYED'.
(Other definitions for starry-eyed that I've seen before include "Out of touch with reality" , "Naively enthusiastic" , "Romantically optimistic" , "Naively idealistic" , "Full of unsophisticated optimism" .)