Request to circulate tires out star (8)
I believe the answer is:
asterisk
'star' is the definition.
(I know that star can be written as asterisk)
'request to circulate tires out' is the wordplay.
'request' becomes 'ask' (to ask is to request something).
'to circulate' indicates putting letters inside (some letters go round others).
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'tires' anagrammed gives 'teris'.
'ask' placed around 'teris' is 'ASTERISK'.
(Other definitions for asterisk that I've seen before include "Star-shaped character used in printing" , "Star-shape on the page" , "Sign" , "Star-shaped mark in printing" , "Star for the printer" .)