What is a piece of timber, or something commonly made of timber; -- used in composition, as in axletree, boottree, chesstree, crosstree, whiffletree, and the like called?

tree — A piece of timber, or something commonly made of timber; -- used in composition, as in axletree, boottree, chesstree, crosstree, whiffletree, and the like. (Webster's 1913.)

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