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(or″thō-mō-lĕk′ū-lăr) Indicating the normal chemical constituents of the body or the restoration of those constituents to normal.


(or″thō-mik″sŏ-vī′rŭs) [ortho- +myxo- + virus] Any of a family (Orthomyxoviridae) of single-stranded RNA viruses that include the influenza viruses. SEE: paramyxovirus.


(or′thŏ-pan″tŏ-gram″) [ortho- + panto- + -gram] ABBR: OPG. A panoramic x-ray of all the teeth and the surrounding bones of the face and jaw. It is obtained by rotating the imaging source around the front of the mouth and is used for orthodontic assessments, evaluations of the wisdom teeth, and periodontal imaging.

orthopedic, orthopaedic

(or″thō-pē′dĭk) Concerning the prevention or correction of bone, joint, ligament, and muscular disorders.

orthopedics, orthopaedics

(or″thō-pē′dĭks) [″ + pais, child] The branch of medical science that deals with prevention or correction of disorders involving locomotor structures of the body, esp. the skeleton, joints, muscles, fascia, and other supporting structures such as ligaments and cartilage.

orthopedic technician

A health care professional who is skilled in maintaining traction devices, applying traction, making casts, and applying splints.

orthopedist, orthopaedist

(or″thō-pē′dĭst) A specialist in orthopedics.


(or″thō-fō′rē-ă) [″ + pherein, to bear] Coordination (alignment) of the visual axes.


(or-thof″thăl-al′dĭ-hīd″) [ortho- + (na)phthal(ene) + aldehyde] ABBR: OPA. A microbicidal chemical used to disinfect surfaces, endoscopes, and other heat-sensitive instruments.

image Personnel who use OPA must wear gloves, goggles, and gowns to prevent contact with mucous membranes or skin.


(or″thŏp′nē-ă) [″ + pnoia, breath] Labored breathing that occurs when lying flat and improves when standing or sitting up. This is one of the classic symptoms of left ventricular heart failure, although it occasionally occurs in other cardiac or respiratory illnesses.


(or″thŏ-poks′vī-rŭs) A genus of virus that includes the viruses that cause smallpox (variola), cowpox, and monkeypox.


(or″thō-sī-kī′ă-trē) [ortho- + psychiatry] The branch of psychiatry concerned with mental and emotional development, esp. of young people.


(or-thŏp′tĭk) [″ + optikos, pert. to vision] Pert. to or producing normal binocular vision.


1. The science of correcting defects in binocular vision resulting from defects in optic musculature. 2. The technique of eye exercises for correcting faulty eye coordination affecting binocular vision. The technique is also referred to as orthoptic training.


A health care professional who specializes in ...

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