PAHOEHOE
pahoehoe
(noun) freely flowing lava
Source: WordNet® 3.1
Etymology
Noun
pahoehoe (plural pahoehoes)
A form of lava flow of basaltic rock, usually dark-colored with a smooth or ropey surface. It is one of two chief forms of lava flow emitted from volcanoes of the Hawaiian type, the other form being aa.
Source: Wiktionary
Pa*ho"e*ho`e, n. (Min.)
Definition: A name given in the Sandwich Islands to lava having a
relatively smooth surface, in distinction from the rough-surfaced
lava, called a-a.
Source: Webster’s Unabridged Dictionary 1913 Edition