Webster's Revised Unabridged Dictionary · 1913

Dense

Dense , adjective

[Latin densus; akin to Greek dasy` thick with hair or leaves: compare French dense.]

1.
Having the constituent parts massed or crowded together; close; compact; thick; containing much matter in a small space; heavy; opaque; as, a dense crowd; a dense forest; a dense fog.
All sorts of bodies, firm and fluid, dense and rare. — Ray
To replace the cloudy barrier dense. — Cowper
2.
Stupid; gross; crass; as, dense ignorance.