Overlap

Part of speech: noun (n.)

1. The lapping of one thing over another; as, an overlap of six inches; an overlap of a slate on a roof.

2. An extension of geological beds above and beyond others, as in a conformable series of beds, when the upper beds extend over a wider space than the lower, either in one or in all directions.

Part of speech: verb (v.)

To lap over; to lap.