Excellent upright character with article favouring gradual change (6)
I believe the answer is:
fabian
'favouring gradual change' is the definition.
I can't judge whether this defines the answer.
'excellent upright character with article' is the wordplay.
'excellent' becomes 'fab' (slang abbreviation of fabulous).
'upright character' becomes 'I' (vertical letter of the alphabet).
'with' says to put letters next to each other.
'article' becomes 'an' (indefinite article).
'fab'+'i'+'an'='FABIAN'
Can you help me to learn more?
(Other definitions for fabian that I've seen before include "Sainted pope" , "Member of a socialist society, founded 1884" , "cautious" , "who belongs to a left-wing society" , "Patient left winger" .)