STALAGMITE
stalagmite
(noun) a cylinder of calcium carbonate projecting upward from the floor of a limestone cave
Source: WordNet® 3.1
Etymology
Noun
stalagmite (plural stalagmites)
(geology) A secondary mineral deposit of calcium carbonate or other mineral, in shapes similar to icicles, that lie on the ground of a cave.
Source: Wiktionary
Sta*lag"mite, n. Etym: [Gr. stalagmite.] (Geol.)
Definition: A deposit more or less resembling an inverted stalactite,
formed by calcareous water dropping on the floors of caverns; hence,
a similar deposit of other material.
Source: Webster’s Unabridged Dictionary 1913 Edition