Rustic couple get left behind (5)

I believe the answer is:

yokel

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'rustic' is the definition.
(I know that yokel is a type of rustic)

'couple get left behind' is the wordplay.
'couple' becomes 'yoke' (synonyms).
'get left behind' becomes 'l' (I can't explain this - if you can you should give a lot more credence to this answer).
'yoke'+'l'='YOKEL'

Can you help me to learn more?

(Other definitions for yokel that I've seen before include "Simple rustic" , "Rustic - peasant" , "Country bumpkin" , "Hayseed" , "Countryman" .)

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

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