- 1. Symbol for oxygen; orotidine. 2. Abbreviation for opening (in formulas for electrical reactions). 3. Symbol for a blood group in the ABO system. See ABO blood group, Blood Groups appendix. 4. An abbreviation derived from ohne Hauch (without a film), used as a designation for: 1) antigens that occur in the bacterial cell, in contrast to those in the flagella; 2) specific antibodies for such somatic antigens; 3) the agglutinative reaction between somatic antigen and its antibody.* * *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
* * *O abbr1) opening2) [Latin octarius] pint used in writing prescriptionsO symbol oxygenO 'ō n the one of the four ABO blood groups characterized by the absence of antigens designated by the letters A and B and by the presence of antibodies against these antigens
* * *ohne Hauch; oxygen.
Medical dictionary. 2011.