Drifting, leaderless, anchorless right away in lake (4,4)

I believe the answer is:

loch ness

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'lake' is the definition.
(I know that Loch Ness is a loch)

I cannot understand how the rest of the clue works.

(Other definitions for loch ness that I've seen before include "Scottish lake with mysterious monster" , "Scottish monster's home" , "where monster lurks?" , "deep water" , "monstrous location?" .)

I've seen this clue in The Everyman puzzle in The Observer.

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