Means of transport sometimes sprung (4)

I believe the answer is:

trap

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'means of transport' is the definition.
'trap' can be an answer for 'transport' (trap is a kind of transport). I am not certain of the 'means of' bit.

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for trap that I've seen before include "Control ball" , "two-wheeler" , "website?" , "Catch; two-wheeled carriage" , "Light horse-drawn carriage" .)

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

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