| NPV | negative predictive value; pressure value; negative pressure ventilation; net present value; nuclear... |
|---|---|
| OAP | Office of Adolescent Pregnancy; old age pension, old age pensioner; ophthalmic artery pressure; oste... |
| OP | occipitoparietal; occipitoposterior; occiput posterior; octapeptide; olfactory peduncle; opening pre... |
| OPP | osmotic pressure of plasma; oxygen partial pressure |
| pa-pv | pulmonary arterial pressure-pulmonary venous pressure |