Bit of a rush during a race, you can be sure (5)
I believe the answer is:
trust
'bit' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for trust that I've seen before include "Rely on" , "Place confidence in or reliance on" , "responsibility" , "Faith; care" , "Hope, expect" .)