Word Study
superphosphate
CIDE DICTIONARY
superphosphate, n.
An acid phosphate. [1913 Webster]
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.
OXFORD DICTIONARY
superphosphate, n. a fertilizer made by treating phosphate rock with sulphuric or phosphoric acid.
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