Search Result for "pillow lava":
Wordnet 3.0

NOUN (1)

1. lava that hardened in rounded shapes suggestive of pillows; believed to result from underwater eruptions; 



WordNet (r) 3.0 (2006):

pillow lava
    n 1: lava that hardened in rounded shapes suggestive of pillows;
         believed to result from underwater eruptions