v. t. [ imp. & p. p. Dephlogisticated p. pr. & vb. n. Dephlogisticating. ] [ Pref. de- + phlosticate: cf. F. déphlogistiguer. ] (O. Chem.) To deprive of phlogiston, or the supposed principle of inflammability. Priestley. [ 1913 Webster ]

Dephlogisticated air, oxygen gas; -- so called by Dr. Priestly and others of his time.

-- De`phlo*gis`ti*ca"tion n. [1913 Webster]