The mineral form of calcium nitrate

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Nitrocalcite \Ni`tro*cal"cite\, n. [Nitro- + calcite.] (Min.) Nitrate of calcium, a substance having a grayish white color, occuring in efflorescences on old walls, and in limestone caves, especially where there exists decaying animal matter.

Wiktionary Word definitions in Wiktionary
n. (context mineralogy English) A hydrated calcium nitrate mineral that forms as an efflorescence where manure contacts concrete or limestone in a dry environment, as in stables or caverns.

WordNet Word definitions in WordNet
n. the mineral form of calcium nitrate