Move heavily, carrying useless furniture, say? (6)

I believe the answer is:

lumber

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'move heavily' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for lumber that I've seen before include "Move awkwardly - unwanted household items" , "Jumble" , "Move clumsily - Jack's wood?" , "Move awkwardly; useless things" , "Stored furniture; (US) timber" .)

I've seen this clue in The Irish Times.

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