Rough calculation provided by one male in big car (8)
I believe the answer is:
estimate
'rough calculation' is the definition.
(I've seen this in another clue)
'one male in big car' is the wordplay.
'one' becomes 'i' (Roman numeral).
'male' becomes 'm' (common abbreviation).
'in' means one lot of letters goes inside another.
'big car' becomes 'estate' (type of car. I am not sure about the 'big' bit.).
'i'+'m'='im'
'im' inserted within 'estate' is 'ESTIMATE'.
'provided by' acts as a link.
Can you help me to learn more?
(Other definitions for estimate that I've seen before include "Calculate in approximate way" , "Meatiest (anag) - figure" , "Statement of expected cost" , "Guess, rough calculation" , "Judge the approximate value" .)