You ultimately number one chap, as befits a wonderful dream? (7)
I believe the answer is:
utopian
'a wonderful dream?' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'you ultimately number one chap as befits' is the wordplay.
I cannot really see how this works, but
'you' could be 'u' (I've seen this in other clues) and 'u' is found in the answer.
'number' could be 'i' (I is an example) and 'i' is located in the answer.
'one' could be 'an' (I've seen this in other clues) and 'an' is found in the answer.
The remaining letters 'top' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for utopian that I've seen before include "Just perfect, as in Thomas More's ideal country" , "Thomas More-ish?" , "Impractically idealistic" , "Fantastic" , "Of an ideal existence" .)