Checks to cover origin of narrow openings (5)

I believe the answer is:

vents

'openings' is the definition.
(vent is a kind of opening)

'checks to cover origin of narrow' is the wordplay.
'checks' becomes 'vets' (I've seen this before).
'to cover' means one lot of letters goes inside another.
'origin of' suggests taking the first letters.
The first letter of 'narrow' is 'n'.
'vets' going around 'n' is 'VENTS'.

(Another definition for vents that I've seen is " Escape holes for gas or air".)

I've seen this clue in The Telegraph.

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