Crossword Genius

Collide briefly with runners when cycling (4)

Ross

I believe the answer is:

kiss

'collide briefly with' is the definition.
(kiss can mean to brush against or hit softly)

I cannot understand how the rest of the clue works.

(Other definitions for kiss that I've seen before include "Smooch" , "Evidence of romance" , "Snog" , "Greet with lips" , "Embrace" .)

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