Accidentally pass by rough dwelling on narrow strip of land (7)

I believe the answer is:

isthmus

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'narrow strip of land' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for isthmus that I've seen before include "Connective strip of land" , "Narrow land bridge" , "This sum for a narrow piece of land" , "Narrow strip of land in sea" , "Tongue" .)

I've seen this clue in The Irish Times.

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