Webster’s Revised Unabridged Dictionary · 1913
Effusive
Ef·fu′sive (ĕf·fū′sĭv), a. Pouring out; pouring forth freely. "Washed with the effusive wave." Pope.
Effusive rocks (Geol.), volcanic rocks, in distinction from so-called intrusive, or plutonic, rocks.
— Ef·fu′sive·ly, adv. — Ef·fu′sive·ness, n.