Finally ad caused a run on revolutionary mousetrap? (7)
I believe the answer is:
cheddar
'mousetrap?' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'finally ad caused a run on revolutionary' is the wordplay.
'finally' suggests the final letters.
'run' becomes 'r' (cricket abbreviation).
'on' is a charade indicator (letters next to each other).
'revolutionary' becomes 'che' (Che Guevara the Marxist revolutionary).
The final letters of 'ad caused' are 'dd'.
'dd'+'a'+'r'='ddar'
'ddar' put after 'che' is 'CHEDDAR'.
Can you help me to learn more?
(Other definitions for cheddar that I've seen before include "Cheese; Somerset town" , "Kind of cheese" , "Hard cheese" , "Somerset village" , "part of ploughman's lunch" .)