Unsteady dog? (7)

I believe the answer is:

lurcher

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'dog?' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for lurcher that I've seen before include "inclined to leave people in difficulties?" , "incapable of steady gait?" , "a hunting animal" , "Crossbred hunting dog" , "Crossbred hunter" .)

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

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