Ideal article on posh tropical headgear (7)
I believe the answer is:
utopian
'ideal' is the definition.
(similar in meaning)
'article on posh tropical headgear' is the wordplay.
'article' becomes 'an' (indefinite article).
'on' means one lot of letters go next to another.
'posh' becomes 'u' (abbreviation for upper-class - opposite to non-U).
'tropical headgear' becomes 'topi' (topi is a kind of headgear. I am not sure about the 'tropical' bit.).
'u'+'topi'='utopi'
'an' put after 'utopi' is 'UTOPIAN'.
Can you help me to learn more?
(Other definitions for utopian that I've seen before include "Thomas More-ish?" , "I put on a show of perfect kind" , "Unworkable" , "Of supposed perfection" , "Of an ideal existence" .)