Other forms: sprawled; sprawls
When you sprawl, you spread out in an ungainly way, like when you're lying down comfortably on the sofa with your legs and arms flung out around you.
As a noun, the most common use of this word nowadays is in the phrase "urban sprawl" (or "suburban sprawl"), which describes municipal development — things like new neighborhoods, shopping malls, and office complexes — that spreads out of control, according to no approved plan, and usually with pretty ugly results.