• Specialty
  • Cardiology
  • Dentistry
  • Dermatology
  • General Medicine
  • GI/GU
  • Hematology
  • Immunology
  • Lab Medicine & Pathology
  • Neuro-Psych
  • OB-Gyn
  • Oncology
  • Ophthalmology
  • Orthopaedic
  • Otolaryngology - ENT
  • Radiology
  • Surgery

• General Medicine
  • Diabetes Related Terms
  • Epidemiology Terms
  • General Medicine Terms
  • Sample Reports - General Medicine
  • Sample Reports - Allergy / Immunology
  • Sample Reports - Endocrinology

• General Medicine Terms

- O -

• Obstruction

Blockage in the gastrointestinal tract that prevents the flow of liquids or solids.



• Occluded artery

An artery that is narrowed by plaque that impedes blood flow.



• Occult

Disease or symptoms that are not readily detectable by physical examination or laboratory tests.



• Occult bleeding

Blood in stool that is not visible to the naked eye.



• Ocular hypertension

High (greater than 21 mm Hg) intraocular pressure.



• Odorant

Substance that stimulates the sense of smell.



• Olfaction

The act of smelling.



• Olfactometer

Device for estimating the intensity of the sense of smell.



• Oncogenes

Genes that promote normal cell division.



• Oncogenes

Genes that normally play a role in the growth of cells but, when over expressed or mutated, can foster the growth of cancer.



• Oncologist

A physician who specializes in treating cancer, including surgical oncologist, radiation oncologist, pediatric oncologist, gynecologic oncologist, and medical oncologist.



• Oncologist

A doctor who specializes in treating cancer.



• On-off effect (ON-OFF PHENOMENA)

A change in the patient's condition, with sometimes rapid fluctuations between uncontrolled movements and normal movement, usually occurring after long-term use of levodopa and probably caused by changes in the ability to respond to this drug.



• Oophorectomy

Surgery to remove one or both ovaries.



• Open surgery

Cutting the skin and tissues during surgery to expose a full view of the structures and organs involved in the procedure.



• Open-set speech recognition

Understanding speech without visual clues.



• Optional surgery

An operation the patient chooses to have done, which may not be essential to the continuation or quality of life. (See also elective surgery.)



• Oral and maxillofacial surgeon

Orthopaedic facial surgeon who is responsible for treating a wide variety of dental problems, including the removal of impacted teeth and reconstructive facial surgery.



• Oral dissolution therapy

Method of dissolving cholesterol gallstones.



• Orchiectomy (CASTRATION)

The surgical removal of the testicles.



• Oropharynx

The part of the throat at the back of the mouth.



• Orthodontics

Orthodontics is the dental specialty that focuses on the development, prevention, and correction of irregularities of the teeth, bite, and jaw.



• Orthokeratology

The use of contact lenses to change the shape of the cornea in order to correct refractive error.



• Orthopaedic surgeon (ORTHOPAEDIST)

The physician who diagnoses, treats, and manages the rehabilitation process, and provides prevention protocols for patients who suffer from injury or disease in any of the components of the musculoskeletal system.



• Orthopaedic surgery (ORTHOPAEDICS)

The medical specialty devoted to the diagnosis, treatment, rehabilitation, and prevention of injuries and diseases of the body's musculoskeletal system.



• Orthostatic hypotension

A large decrease in blood pressure upon standing; may result in fainting.



• Osmolality

Osmotic concentration. An indicator of fluid balance in the bodies tissues.



• Osteitis pubis

Inflammatory reaction in the pubic symphysis, usually as a result of overuse; pain is felt in the groin region, thigh, lower abdomen, and around the perineal structures.



• Osteoblast

Cell found in bone; its function is to form the tissue and minerals that give bone its strength.



• Osteoclast

Very large cell formed in bone marrow; its function is to absorb and remove unwanted tissue.



• Osteocyte

Cell found within the bone; its function is to help maintain bone as living tissue.



• Osteophyte

An outgrowth of bone.



• Otoacoustic emissions

Low-intensity sounds produced by the inner ear that can be quickly measured with a sensitive microphone placed in the ear canal.



• Otolaryngologist

Physician/surgeon who specializes in diseases of the ears, nose, throat, head, and neck.



• Otologist

Physician/surgeon who specializes in diseases of the ear.



• Otosclerosis

Abnormal growth of bone in the inner ear, which prevents structures within the ear from working properly, resulting in a gradual loss of hearing.



• Ototoxic drugs

Drugs that can damage the hearing and balance organs located in the inner ear.



• Outer ear

External portion of the ear, consisting of the pinna, or auricle, and the ear canal.



• Outpatient surgery

Surgery which allows the patient to go home the same day.



• Ovaries

Pair of small glands, located on either side of the uterus, in which egg cells develop and are stored and the female sex hormones estrogen and progesterone are produced.



• Overflow incontinence

The leakage of small amounts of urine from a bladder that is always full.



• Overlapping clones

See genomic library.



• Ovulation

Release of a mature egg from an ovary.



• Oxytocin

Hormone produced by the pituitary gland that stimulates contractions of the uterus during labor and release of milk during breastfeeding.