sta·lac·tite (stə-lāk'tīt', stāl'ək-) n. An icicle-shaped mineral deposit, usually calcite or aragonite, hanging from the roof of a cavern, formed from the dripping of mineral-rich water.
[New Latin stalactītēs, from Greek stalaktos, dripping, from stalassein, stalak-, to drip.] sta·lac'ti·form' adj., stal'ac·tit'ic (stāl'āk-tĭt'ĭk, stə-lāk'-) adj.