Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!


Capital of the Greek letter omega. Symbol for ohm.


Lower-case Greek letter omega.


1. Symbol for the element oxygen. 2. oculus, eye. 3. Symbol for a particular blood type. 4. The diameter of a suture.

PATIENT CARE: The greater the number of O's, the smaller the diameter of the suture. Thus, a 6-O or 7-O suture is used for delicate surgeries, e.g., in plastic surgery on the face. A 3-O or 4-O suture is wider and stronger, may be used to close a deep laceration on a limb or the trunk but is more likely to leave a scar.


Symbol for the molecular formula for oxygen.


Symbol for ozone.


occiput anterior; ongoing assessment


otoacoustic emissions test.


osteoclast activating factor.

oak bark

(ōk bark) The external layer of woody plants of the genus Quercus, sometimes used by alternative medicine practitioners as an anti-inflammatory and antidiarrheal.


An acronym for describing a form of psychotherapy that encourages people to better understand their problems and take responsibility for them: Open-ended questions; Affirming statements; Reflective listening; and concluding with a Summary.


Outcome and assessment information set.


(ō-ā′sĭs,′ō-ā′sēz″) pl. oases [Gr. oasis, a fertile area in an arid region, oasis] An area of healthy tissue surrounded by a diseased portion.


(ōt) Grain or seed of a cereal grass (Avena sativa) used as food.


(ōth) A solemn attestation or affirmation. SEE: Hippocraticoath; Nightingale Pledge.


(ōt′mēl″) Ground, rolled, or steel-cut oats from which a cereal can be made. Oatmeal has several therapeutic uses. In the diet, it provides fiber, lowers cholesterol levels, and can safely be consumed by patients with wheat allergies or celiac sprue because it has no gliadin (a prolamin). Oatmeal is also sometimes used in tepid baths or soaps to sooth inflamed or irritated skin.




(ō-bom′ă-kar″) Patient Protection and Affordable Care Act.

Ober test

(ō′bĕr) [Frank Roberts Ober, U.S. orthopaedic surgeon, 1881–1960] 1. A clinical test for tightness of the iliotibial band. The patient lies on the uninvolved side ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.