sta·lag·mite 
(stə-lăgmīt′, stăləg-)
(stə-lăgmīt′, stăləg-)n.
A conical mineral deposit, usually calcite or aragonite, built up on the floor of a cavern, formed from the dripping of mineral-rich water.
[New Latin stalagmītēs, a drop, from Greek stalagma, a drop, or stalagmos, dropping, both from stalassein, stalak-, to drip.]
stal′ag·mitic (stăl′əg-mĭtĭk, stə-lăg′-) adj.