Mark part of the intestine (5)

I believe the answer is:

colon

I believe this clue is a double definition.

'mark' is the first definition.
(I know that colon is a type of punctuation)

'part of the intestine' is the second definition.
(I know that colon is part of large intestine)

(Other definitions for colon that I've seen before include "cash" , "City at the Caribbean entrance to the Panama Canal" , "Panamanian port" , "Stop (less than full)" , "Stop (on the inside!)" .)

I've seen this clue in The Telegraph.

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