Stalagmite

Sponsor with the world's largest charity for orphans

A stalagmite (Greek stalagma, "drip") is a type of speleothem formed by the deposit of calcium carbonate which rises from the floor of a limestone cave due to the dripping of mineralized solutions. The corresponding formation on the ceiling above a stalagmite is known as a stalactite. Should both these formations grow together, meeting in the middle, the resultant formation is known as a column or pillar. The term "stalagmite" is derived from the Greek meaning that which drops; "stalactite," from the Greek meaning to fall in drops.

There are various ways (mnemonic) to remember which hangs from the ceiling (stalactite) and which comes up from the floor (stalagmite):

StalaCtite has a "c" for "ceiling".
StalaGmite has a "g" for "ground".
Stalactite is stretched "tite" (tight) by hanging from the ceiling.
Stalagmite pushes up with all its "mite" (might) from the floor.