Medical Glossary
Terms starting with O
- ConstipationObstipation
- Obstipation is the medical term for constipation, that is, infrequent and difficult bowel movements. Common causes are a diet low in fibre, drinking too little, lack of exercise or certain medications.
- EdemaÖdem
- An oedema is a swelling caused by fluid that accumulates in the tissue — often in the legs or ankles. Causes range from prolonged standing to problems with the heart, kidneys or veins.
- ENTORL
- ORL is the abbreviation commonly used in French-speaking regions for oto-rhino-laryngology, that is, ear, nose and throat medicine. It treats disorders of the ears, nose, throat and larynx.
- EsophagitisÖsophagitis
- Oesophagitis is an inflammation of the oesophagus, frequently caused by stomach acid rising up (reflux). Typical complaints are heartburn, pain behind the breastbone and difficulty swallowing.
- EsophagogastroduodenoscopyÖsophagogastroduodenoskopie
- Oesophagogastroduodenoscopy is an examination of the oesophagus, stomach and duodenum using a flexible tube with a camera. It is used to investigate complaints such as heartburn, bleeding or stomach pain.
- EsophagusÖsophagus
- The oesophagus is the gullet, the muscular tube that transports food from the throat into the stomach. Conditions such as heartburn or inflammation frequently affect its lower end.
- ObstructionObstruktion
- Obstruction refers to the narrowing or blockage of a hollow organ or passage, such as the airways or the bowel. With airway obstruction, breathing out is difficult, as in asthma or COPD.
- OcclusionOkklusion
- Occlusion means closure and is used differently depending on the specialty: in dentistry it refers to the way the rows of teeth bite together, in vascular medicine to the blockage of a blood vessel.
- OdontogenicOdontogen
- Odontogenic means «originating from the teeth» and describes complaints or infections that have their origin in a tooth or the tooth-supporting structures. An odontogenic abscess arises, for example, from an inflammation of a tooth root.
- Off-label useOff-Label-Use
- Off-label use refers to the use of a medicine outside the officially approved indication, age group or dosage. It can be appropriate when no approved alternative is available, but it requires careful medical consideration.
- OliguriaOligurie
- Oliguria refers to a reduced production of urine, in which the amount passed each day is clearly below normal. It can indicate a lack of fluids or impaired kidney function.
- OncogenicOnkogen
- An oncogene is an altered gene that can promote the development of cancer by driving cell growth without restraint. A normal gene that controls growth becomes such a cancer gene through mutation.
- OncologistOnkologe
- An oncologist is a doctor specialising in cancer diseases. They plan and accompany the treatment of tumours, for example with medication or in cooperation with other specialties.
- OncologyOnkologie
- Oncology is the medical specialty concerned with the development, diagnosis and treatment of cancers. This includes procedures such as chemotherapy, targeted therapies and tumour follow-up care.
- OnychomycosisOnychomykose
- Onychomycosis is a fungal infection of the finger or toe nails, showing itself through thickening, discolouration and brittleness. It often occurs together with athlete's foot.
- OophorectomyOophorektomie
- Oophorectomy is the surgical removal of one or both ovaries, for example in the case of tumours, cysts or as a preventive measure when there is an increased risk of cancer. If both ovaries are removed, women who have not yet reached the menopause enter it prematurely.
- OphthalmologyOphthalmologie
- Ophthalmology is the medical specialty dealing with diseases and injuries of the eye. It covers conditions such as cataract, glaucoma and retinal diseases.
- Orchitis
- Orchitis is an inflammation of the testicle, often caused by viruses or bacteria. Typical signs are swelling, pain and redness; a well-known cause is the mumps virus.
- OrthopedicsOrthopädie
- Orthopaedics deals with diseases and injuries of the musculoskeletal system, that is, of bones, joints, ligaments, tendons and muscles. Conditions treated include osteoarthritis, back problems and bone fractures.
- OsteoarthritisOsteoarthrose
- Osteoarthritis is the age-related or overuse-related wear of joint cartilage, which leads to pain and stiffness. Commonly affected are the knees, hips and finger joints.
- Osteoblast
- Osteoblasts are the cells that build new bone by forming bone substance. Together with the bone-degrading osteoclasts, they keep bone in a constant state of remodelling.
- OsteoclastOsteoklast
- Osteoclasts are large cells that break down old bone substance and thus make bone remodelling possible. An excess of their activity contributes to osteoporosis.
- OsteomalaciaOsteomalazie
- Osteomalacia is a softening of the bones in adults, usually due to a lack of vitamin D. The equivalent condition in childhood is rickets.
- Osteomyelitis
- Osteomyelitis is an inflammation of the bone and bone marrow, usually caused by bacteria. It can occur acutely with fever and pain, or take a chronic course.
- OsteopeniaOsteopenie
- Osteopenia describes a slightly reduced bone density that has not yet reached the extent of osteoporosis. It is considered a preliminary stage and a warning sign of an increased risk of bone fractures.
- OsteoporosisOsteoporose
- Osteoporosis is a disease in which the bones lose density and strength and therefore break more easily. It occurs particularly in women after the menopause and in older age.
- OsteosynthesisOsteosynthese
- Osteosynthesis refers to the surgical stabilisation of bone fractures using plates, screws, nails or wires. It holds the fragments in the correct position until the bone has healed together.
- OsteotomyOsteotomie
- An osteotomy is the surgical cutting and realignment of bone in order to correct malalignment. It is used, for example, in knock knees or bow legs to relieve strain on the joints.
- Otitis externa
- Otitis externa is an inflammation of the outer ear canal, often occurring after contact with water or irritation. Typical signs are itching, pain when the ear is pulled, and a weeping ear canal.
- Otitis media
- Otitis media is an infection of the middle ear that is particularly common in children. It causes earache, fever and sometimes reduced hearing, and often follows a cold.
- OtoscopyOtoskopie
- Otoscopy is the examination of the ear canal and eardrum using an otoscope, an illuminated funnel-shaped instrument. It is used, for example, to investigate earache or a middle ear infection.
- Ovarian cystOvarialzyste
- An ovarian cyst is a fluid-filled cavity on the ovary. Such cysts are usually benign and often disappear on their own, but they can occasionally cause pain or menstrual cycle disturbances.
- OvaryOvar
- The ovary is the female reproductive organ that produces egg cells and sex hormones. The two ovaries lie in the pelvis on either side of the uterus.
- Ovulation
- Ovulation is the release of a mature egg cell from the ovary. It takes place around the middle of the menstrual cycle and marks the fertile days.
- OximetryOximetrie
- Oximetry is the measurement of the oxygen content of the blood, usually painlessly with a clip on the finger (pulse oximetry). It helps to monitor lung and circulatory function.
- OxygenationOxygenierung
- Oxygenation refers to the uptake of oxygen into the blood in the lungs. How well it is working can be measured, for example, with a pulse oximeter on the finger.
- Oxytocin
- Oxytocin is a hormone produced by the body that, among other things, promotes labour contractions and the flow of milk during breastfeeding. It also plays a role in bonding and social behaviour.