Defn: An apparatus employed to indicate the presence, or the amount, of ozone.

OZONOSCOPIC
O*zo`no*scop"ic, a. Etym: [Ozone + Gr. (Chem.)

Defn: Serving to indicate the presence or the amount of ozone.

OZONOUS
O"zo*nous, a.

Defn: Pertaining to or containing, ozone.

P
P (pe),

Defn: the sixteenth letter of the English alphabet, is a nonvocal consonant whose form and value come from the Latin, into which language the letter was brought, through the ancient Greek, from the Phonician, its probable origin being Egyptian. Etymologically P is most closely related to b, f, and v; as hobble, hopple; father, paternal; recipient, receive. See B, F, and M.

See Guide to Pronunciation, §§ 247, 248, and 184-195.

PA
Pa (pä), n.

Defn: A shortened form of Papa.