S1T1R1A1T1O1V4O1L1C3A1N1O1
18 points
STRATOVOLCANO is validvalid
[n STRATOVOLCANOES, STRATOVOLCANOS]
a composite volcano, composed of alternating layers of lava and pyroclastic material, along with abundant dikes and sills [n STRATOVOLCANOES or STRATOVOLCANOS]