oxygen mask

mask placed over the nose and mouth through which a person can breathe oxygen, eg in an aircraft or hospital 氧气面具; 氧气罩: Oxygen masks are used in aircraft only in emergencies. 飞机上的氧气面具只用於紧急情况.

own goal, owner, owner-driver, owner-occupied, owner-occupier, ownerless, ownership, ox, ox-eye, Oxbridge, Oxfam, Oxford, oxidation, oxide, oxidize, oxidize, oxidise, Oxon, oxtail, oxy-acetylene, oxygen, oxygen tent, oxygenate, oxymoron, oyez, oyster, oyster bed, oyster-catcher, oz, ozone, ozone layer, P, P and O, p and p, P, p, p.a. system, p.m., P.M./p.m., pa, pace, pacemaker,