E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Lubbers Hole.
A lazy cowardly way of doing what is appointed, or of evading duty. A seamans expression. Sailors call the vacant space between the head of a lower-mast and the edge of the top, the lubbers hole, because timid boys get through this space to the top, to avoid the danger and difficulties of the futtock shrouds.