Instrument, old, in a car travelling (7)
I believe the answer is:
ocarina
'instrument' is the definition.
(I know that Ocarina is a type of wind)
'old in a car travelling' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'travelling' is an anagram indicator.
'in'+'a'+'car'='inacar'
'inacar' with letters rearranged gives 'carina'.
'o'+'carina'='OCARINA'
(Other definitions for ocarina that I've seen before include "Egg-shaped wind instrument with finger holes" , "toy instrument" , "Small egg-shaped wind instrument with holes for the fingers" , "dated instrument" , "Toy-like wind instrument" .)