pahoehoe

Lava with a smooth ropy surface.

Compact lava. The spongy or rough lava is called a-a.

A name given in Hawaii (formerly the Sandwich Islands) to lava having a relatively smooth or billowing surface, in distinction from the rough-surfaced lava, called aa.

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.

freely flowing lava