How time flies! (7)

I believe the answer is:

elapses

I'm a little stuck... Click here to teach me more about this clue!

'flies' is the definition.
The definition and answer can be both to do with motion as well as being verbs in their -s form.
Perhaps you can see a link between them that I don't see?

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for elapses that I've seen before include "Passes (in time)" , "Slips away" .)

I've seen this clue in The Globe and Mail.

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