Brought up the French angle -- looking after number one (7)
I believe the answer is:
selfish
'looking after number one' is the definition.
Both the answer and definition are adjectives. Maybe there's a link between them I don't understand?
'brought up the french angle' is the wordplay.
'brought up' shows that the letters should be reversed in order (in a down clue, letters go up).
'the french' becomes 'les' (plural form of 'the' in French).
'angle' becomes 'fish' (synonyms).
'les' in reverse letter order is 'sel'.
'sel'+'fish'='SELFISH'
Can you help me to learn more?
(Other definitions for selfish that I've seen before include "Concerned chiefly with one's own interests" , "Self-seeking" , "Egotistical" , "Concerned only with one's personal welfare" , "without consideration" .)