Word Part | Definition |
O2 | oxygen |
OB | obstetrics |
ob- | against |
OB/GYN | obstetrics & gynecology |
obesity | Being too heavy for one's height. |
oblique | A slanting direction. |
obsessive behavior | Repetitive, compulsive behavior. |
obsessive compulsive disorder | An anxiety disorder characterized by recurrent, unwanted obsessions and compulsions. |
obstetr/o | midwife |
obstetrician | A medical doctor specialized in the management of pregnancy, labor and birth |
obstetrics | The branch of medicine concerned with the care of women during pregnancy, parturition, and the puerperium. |
obstipation | Severe constipation caused by obstruction in the intestines. |
obtund | To blunt or deaden pain. |
obturator muscle | Either of the two muscles that cover the outer surface of the anterior wall of the pelvis, responsible for rotating the thighs outward. |
OC | oral contraceptive |
occipital bone | The curved, shield-shaped bone forming the lower rear part of the skull, enclosing the foramen magnum. |
occlusion | The blockage of a blood vessel. |
OCD | obsessive-compulsive disorder |
ochronosis | The discoloration of body tissues,due to a metabolism disorder. |
oct- | eight |
ocul/o | eye |
ocular absorption | Uptake of substances by tissues of the eye. |
ocular hypertension | A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma. |
ocular hypotension | Abnormally low intraocular pressure often related to chronic inflammation. |
oculomotor | Pertaining to or affecting eye movements. |
odont/o | tooth |
odontogenesis | The process of tooth development. |
odontoma | A mixed tumor of odontogenic origin, |
odyn- | pain |
odynophagia | Painful swallowing. |
-oid | resembling |
ointments | A medicated formulation with an oil base |
-ole | small, little |
oleo- | oil |
olfact/o | smell |
olfactory | Relating to the sense of smell. |
olfactory bulb | The area of the forebrain where the olfactory nerves terminate. |
olfactory nerve | The first cranial nerve. The olfactory nerve conveys the sense of smell. |
olig/o | few, scanty |
oligodontia | Absence of some teeth. |
oligohydramnios | A condition of abnormally low amniotic fluid volume. |
oligomenorrhea | Light or infrequent menstrual periods. |
oligospermia | A deficiency of spermatozoa in the semen, defined as a sperm count below 20 million per milliliter semen. |
oliguria | Decreased urinary output. |
om/o | shoulder |
-oma | tumor, neoplasm |
omentum | A double-layered fold of peritoneum that attaches the stomach to other organs in the abdominal cavity. |
omphal/o | umbilicus (navel) |
omphalitis | Inflammation of the umbilicus. |
onc/o | swelling, tumor |
oncocytoma | A rare, benign tumor usually occurring in the parotid glands in older patients. |
oncogene | A mutated gene that causes the transformation of normal cells into cancerous cells. |
oncolysis | Destruction of a neoplasm. |
oncotic | Pertaining to swelling or edema. |
ontogeny | The developmental history of an individual from inception to maturity. |
onych/o | fingernail, toenail |
onychocryptosis | An ingrown toenail. |
onycholysis | Loosening or separation of nail plate from the underlying nail bed. |
onychomycosis | A fungal infection of the nails. |
oophor/o | ovary |
oophorectomy | Surgical removal of an ovary or ovaries. |
oophoritis | Inflammation of the ovary. |
OPD | outpatient department |
operculum | A lid or covering. |
ophry/o | eyebrow |
ophthalm/o | eye |
ophthalmia | Severe inflammation of the eye. |
ophthalmic | Pertaining to the eye. |
ophthalmology | A surgical specialty concerned with the treatment of eye defects and diseases. |
ophthalmoplegia | Paralysis of one or more of the ocular muscles. |
ophthalmoscopy | An examination of the back part of the eye (fundus), which includes the retina, optic disc, choroid, and blood vessels. |
-opia | vision condition |
opiate | A narcotic containing opium or its derivatives. |
opisth- | behind |
opium | The air-dried juice of the unripe seed capsule of the opium poppy. |
opposition | Relation of the position of the thumb to the other fingers. |
-opsy | process of viewing |
opt/o | eye, vision |
optic nerve | The second cranial nerve which conveys visual information from the retina to the brain. |
optic neuritis | Inflammation of the optic nerve. |
optic tract | Nerve fiber originating from the optic chiasm that connects predominantly to the lateral geniculate bodies. it is the continuation of the visual pathway that conveys the visual information originally from the retina to the optic chiasm via the optic nerves. |
optometry | The professional practice of primary eye and vision care that includes the measurement of visual refractive power and the correction of visual defects with lenses or glasses. |
OR | operating room |
or/o | mouth |
oral | Pertaining to the mouth. |
oral hygiene | The practice of personal hygiene of the mouth. It includes the maintenance of oral cleanliness, tissue tone, and general preservation of oral health. |
orbit | Bony cavity that holds the eyeball and its associated tissues and appendages. |
orbital myositis | Inflammation of the extraocular muscle of the eye. It is characterized by swelling. |
orchid/o | testicles |
orchidalgia | Pain in the testicle. |
orchidectomy | Surgical removal of one or both testicles. |
orchiectomy | The surgical removal of one or both testicles. |
orchiopexy | Surgery to move an undescended testicle into the scrotum. |
orchitis | Inflammation of a testis. |
-orexia | appetite |
organ/o | organ |
organelles | Specialized intracellular structure present in eukaryotic cells. |
organogenesis | Formation of differentiated cells and complicated tissue organization to provide specialized functions. |
orgasm | The climax of sexual excitement. |
ori- | mouth |
ORIF | open reduction internal fixation |
oropharynx | The middle portion of the pharynx that lies posterior to the mouth, inferior to the soft palate, and superior to the base of the tongue and epiglottis. |
orth/o | straight |
orthodontics | The dental specialty dealing with correction of dental abnormalities. |
orthopedics | A surgical specialty which treats and corrects injuries, deformities and diseases to the skeletal system and joints. |
orthopnea | Dyspnea when lying flat. |
orthostatic | Pertaining to a erect posture. |
orthotic | A device for correcting an orthopedic problem. Commonly used for the foot. |
orthotic devices | A device used to support, align, or correct deformities of movable parts of the body. |
osche/o | scrotum |
oscill/o | swing |
-ose | a carbohydrate |
OSHA | Occupational Safety and Health Administration |
-osis | abnormal condition |
osm/o | sense of smell |
osmosis | Tendency of fluids to move from the less concentrated to the more concentrated side of a semipermeable membrane. |
oss/e | bone |
oss/i | bone |
osseous | Composed of or resembling bone.
|
ossicle | A small bone, especially of the middle ear. |
ossification | The formation of bone. |
oste/o | bone |
osteitis | Inflammation of the bone. |
osteoarthritis | A progressive, degenerative joint disease, the most common form of arthritis. |
osteoblastoma | A benign, painful, vascular tumor of bone marked by the formation of osteoid tissue, primitive bone and calcified tissue. |
osteochondritis | Inflammation of a bone and its overlaying cartilage. |
osteochondroma | A cartilage-capped benign tumor that often appears as a stalk on the surface of bone. |
osteochondrosis | Any of a group of disorders of the growth ossification centers in children |
osteocytes | Mature osteoblasts that have become embedded in the bone matrix. |
osteogenesis | The process of bone formation. |
osteology | The science that studies the structure and function of bones. |
osteolysis | Dissolution of bone. |
osteoma | A benign, slow growing tumor composed of bone tissue. |
osteomalacia | An interruption of the mineralization of organic bone matrix leading to bone softening, bone pain, and weakness. It is the adult form of rickets. |
osteonecrosis | Death of a bone or part of a bone. |
osteophyte | Bony projection usually found around joints and often seen in arthritis. |
osteoporosis | Reduction of bone mass without alteration in the composition of bone, leading to fractures. |
osteosarcoma | A sarcoma originating in bone-forming cells, affecting the ends of long bones. |
osteosclerosis | An abnormal hardening or increased density of bone tissue. |
osteotomy | Cutting of a bone. |
ostomy | Surgery to create an artificial opening (stoma) into the urinary or gastrointestinal canal. |
OT | occupational therapy |
ot/o | ear, hearing |
otalgia | Ear ache. |
OTC | over-the-counter |
otitis | Inflammation of the ear, which may be marked by pain, fever, hearing disorders and vertigo. |
otitis media | An ear infection of the middle ear, the area just behind the eardrum. |
otolaryngology | A surgical specialty concerned with the study and treatment of disorders of the ear, nose, and throat. |
otology | The study of diseases of the ear. |
otomycosis | A fungal infection of the external auditory canal. |
otopyorrhea | Discharge of pus from ear. |
otorrhea | Ear discharge. |
otosclerosis | A disease of the bones of the middle and inner ear. |
otoscope | An instrument designed to inspect the ear. |
-ous | pertaining to |
ov/o | egg, ovum |
ovari/o | ovary |
ovarian | Pertaining to the ovary. |
ovarian cysts | General term for cysts and cystic diseases of the ovary. |
ovarian neoplasms | Tumors or cancer of the ovary. These neoplasms can be benign or malignant. |
ovary | Either of the sex glands in females. They produce ova and hormones. |
ovulation | The discharge of an ovum from a rupturing follicle in the ovary. |
ovum | A mature haploid female germ cell extruded from the ovary at ovulation. |
ox/i | oxygen |
ox/o | oxygen |
oxa- | oxygen |
oximetry | The determination of oxygen-hemoglobin saturation of blood. |
OXT | oxytocin |
oxy- | sharp, oxygen |
oxygen | An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration. |
oxytocin | A hormone secreted by the pituitary gland. It simulates contraction during labor and the production of milk. |
oz | ounce |
ozone | An unstable, poisonous allotrope of oxygen. |