Paddy has light brown tin-opener - odd! (7)
I believe the answer is:
tantrum
'paddy' is the definition.
(I've seen this before)
'light brown tin-opener odd' is the wordplay.
'light brown' becomes 'tan' (tan is a light brown colour).
'opener' indicates taking the first letters.
'odd' becomes 'rum' (rum can mean strange or dubious).
The first letter of 'tin' is 't'.
'tan'+'t'+'rum'='TANTRUM'
'has' acts as a link.
(Other definitions for tantrum that I've seen before include "Childish angry outburst" , "Childish fit of anger" , "Burst of temper" , "Childish display of temper" , "Fit of childish temper" .)