過磷酸鹽,過磷酸石灰
Superphosphate \Su`per*phos"phate\, n. (Chem.) An acid phosphate. {Superphosphate of lime} (Com. Chem.), a fertilizer obtained by trating bone dust, bone black, or phosphorite with sulphuric acid, whereby the insoluble neutral calcium phosphate, {Ca3(PO4)2}, is changed to the primary or acid calcium phosphate {Ca(H2PO4)2}, which is soluble and therefore available for the soil.