Tiny Frenchman in Aussie vehicle (6)
I believe the answer is:
minute
'tiny' is the definition.
(minute can mean small)
'frenchman in aussie vehicle' is the wordplay.
'frenchman' becomes 'm' (abbreviation for Monsieur - like 'Mr').
'aussie vehicle' becomes 'ute' (Australian abbreviation for utility vehicle).
'm'+'in'+'ute'='MINUTE'
(Other definitions for minute that I've seen before include "Very small; record" , "Small amount of time" , "60 seconds; tiny" , "Barely perceptible" , "Small, tiny" .)