Phosphorous
Pronunciation : Phos"phor*ous
Part of Speech : a.
Etymology : [Cf. F. phosphoreux.] (Chem.)
Definition : Defn: Of or pertaining to phosphorus; resembling or containing phosphorus; specifically, designating those compounds in which phosphorus has a lower valence as contrasted with phosphoric compounds; as, phosphorous acid, H3PO3.
Source : Webster's Unabridged Dictionary, 1913