Line drawn by cartographer, out cavorting in Dingle, for a change (9)

I believe the answer is:

longitude

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'line' is the definition.
(longitude is a kind of line)

I don't understand how the rest of the clue works.

(Other definitions for longitude that I've seen before include "this helps define our position" , "Imaginary circles of distance east or west" , "Distance east or west of the Greenwich meridian" , "Word often paired with latitude" , "Distance in degrees" .)

I've seen this clue in The Irish Times.

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