O

• blood type in the ABO blood group;

• eye [Lat. oculus];

• nonmotile strain of microorganisms [Ger. ohne Hauch];

• no response [pacemaker];

• objective findings;

• observed frequency in a contingency table;

• obstetrics;

• obvious;

• occipital electrode placement in electroencephalography;

• occiput;

• occlusal;

• [doctor's] office;

• often;

• ohm;

• old;

• opening;

• operator;

• operon;

• opium;

• oral, orally;

• orange [color];

• orderly respirations [anesthesia chart];

• ortho-;

• orthopedics;

• osteocyte;

• other;

• output;

• ovine;

• oxygen;

• pint [Lat. octarius];

• respirations [anesthesia chart];

• zero