To lie partially on or over something; to overlap something. A noun or pronoun can be used between "lap" and "over." The two dorm buildings lap over in the common area on the first floor. Make sure each tile laps over the next one, or the roof will leak when it rains.
lap over (something)
[for something] to extend or project over the edge or boundary of something. The lid lapped over the edge of the barrel, forming a little table. The blanket did not lap over enough to keep me warm.