Medical terms A–Z

Too little thyroid hormone.

A pulse oximeter reports how full the hemoglobin is, not how much oxygen the blood holds, and the two can part company.

Oxygen can fail tissue at several points along its journey, and where the failure happens defines the type of hypoxia.

An adjective rather than a diagnosis, it labels how much oxygen a place holds, from a whole body to one tumor core.

Removing the uterus ends the possibility of pregnancy, but on its own it does not bring on menopause.

The original brand of terazosin, a tablet built up in stages because its early doses can drop blood pressure abruptly.

ICD most often refers to an implanted device that corrects dangerous heart rhythms, though the same abbreviation also names an unrelated diagnostic coding system.

ICE is a combination chemotherapy regimen used for certain lymphomas that have returned or resisted earlier lines of treatment.

A drug used to treat certain types of breast cancer in postmenopausal women.

An anticancer drug that stops tumor cells from growing by blocking the ability of cells to make DNA.

A radiolabeled monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment of other types of B-cell tumors.

Idiopathic describes a disease or condition that arises spontaneously without an identifiable cause, despite thorough evaluation.

A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made in organs such as the liver and the spleen, instead of in the bone marrow.

A set of pneumonia-like symptoms (such as fever, chills, coughing, and breathing problems) that occur with no sign of infection in the lung.

A disease in which the alveoli (tiny air sacs at the end of the bronchioles in the lungs) are overgrown with fibrous tissue.

A drug that blocks the effects of estrogen.

An oil and water emulsion mixed with a vaccine to make the immune system respond more strongly to it.

A drug used to treat some infections caused by viruses and several types of cancer.

A test to check for blood in the stool.

Ig is the abbreviation used in laboratory and immunology reports for immunoglobulin, the family of antibody proteins made by immune cells.

The messenger through which growth hormone does its work, since most of what growth hormone achieves is carried out by IGF-1.

A protein found on the surface of some types of cells that binds to insulin-like growth factor (IGF).

A monoclonal antibody linked to a toxic substance.

A substance being studied for its ability to prevent damage to normal tissue caused by radiation therapy.

The numbered vocabulary immune cells use to talk to each other, and the target of a fast growing list of modern drugs.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body.

An opening into the ileum, part of the small intestine, from the outside of the body.

A substance that is being studied as an anticancer drug.

A substance that is being studied as an anticancer drug.

Two letters on a chart that decide how quickly a drug reaches the blood: into muscle, not into a vein or under the skin.

An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

A procedure that uses a computer to create a picture of a tumor to help guide the radiation beam during radiation therapy.

Attention is finite, and the technique works by occupying it, which is why sensory detail matters more than the scene chosen.

Imaging creates pictures of internal body structures using techniques such as x-rays, ultrasound, or magnetic fields, without requiring surgery.

A method of producing pictures of areas inside the body.

A substance being studied in the treatment of breast cancer that has come back.

A substance being studied in the treatment of glioblastoma (a type of brain tumor) that has come back.

A substance being studied in the treatment of some types of cancer.

A rare type of malignant (cancer) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that often contains several different types of tissue such as hair, muscle…

A substance being studied in the treatment of several types of lymphoma.

A substance being studied in the treatment of multiple myeloma and several other types of cancer.

A drug that stimulates the immune system to respond to disease.

Shorthand for how well the body detects, remembers and clears threats, rather than anything a single blood test can report.

A properly functioning immune response distinguishes harmful invaders from the body's own tissue, activating defenses that range from rapid to highly specific.

Defense rests on telling self from everything else, and its recognized failures run in both directions, too little response and too much.

The failure of the immune system to respond to an antigen that previously caused an immune response.

The immune system destroying its own platelets, leaving blood that clots poorly and skin that marks at the lightest knock.

Immunity is the body's capacity to resist a specific infectious agent, arising from prior exposure, vaccination, or the transfer of protective antibodies.

Immunization is the deliberate process of producing protective immunity against a specific infectious disease, most often achieved through vaccination.

Borrowing the immune system's precision to pick one molecule out of blood and measure how much is there.

Immunocompetence is the capacity of the immune system to recognize and respond effectively to infections and other foreign substances.

Having the ability to produce a normal immune response.

Not one condition but many, and which part of the defense is missing predicts which organisms end up causing trouble.

Immunodeficiency can be present from birth due to a genetic cause or develop later in life from illness, medication, or other acquired factors.

The inability of the body to produce an immune response.

Immunoglobulins are antibody proteins produced by immune cells to recognize and bind specific foreign targets such as bacteria, viruses, or toxins.

A staining method that uses antibodies to make one chosen protein visible in a slice of tissue, while everything else stays pale.

A substance used to help boost the immune response to a vaccine so that less vaccine is needed.

Immunology is the scientific study of the immune system, including how it defends against infection and contributes to allergic and autoimmune disease.

Change in the body's immune system, caused by agents that activate or suppress its function.

Reading the badges on a cell surface to work out what the cell is and whether a population came from one ancestor.

An imaging procedure in which antibodies labeled with radioactive substances are given to the person.

A substance that increases the ability of the immune system to fight infection and disease.

Immunosuppression is a reduced state of immune system activity that can be caused deliberately by treatment or by underlying disease.

Immunosuppressive describes a drug, therapy, or condition that reduces the activity of the body's immune system.

Therapy used to decrease the body's immune responses, such as drugs given to prevent transplant rejection.

Rather than attacking a disease directly, these treatments change what the immune system is willing to attack, or willing to tolerate.

An antibody linked to a toxic substance.

Loperamide, marketed as Imodium, slows intestinal movement to treat diarrhea by allowing more fluid to be absorbed from the stool.

A loss of part or all of a physical or mental ability, such as the ability to see, walk, or learn.

A substance or object that is put in the body as a prosthesis, or for treatment or diagnosis.

A procedure used to do a mammogram (x-ray of the breasts) in women with breast implants.

A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor.

A small device installed under the skin to administer a steady dose of drugs.

An erection depends on blood flow, so difficulty with it can be the first outward sign of narrowing arteries elsewhere.

Applied to a person rather than to a function, which is precisely why clinical writing dropped the adjective in favor of a phrase.

Radiation shaped to the tumor rather than aimed at a box around it, using beams whose strength varies across their own width.

A radiolabeled monoclonal antibody that is used to detect certain types of B-cell non-Hodgkin lymphoma and is being studied in the detection of other types of B-cell tumors.

In situ describes something found or observed in its original, natural location, without having moved, spread, or been removed from that place.

A label recording where a result came from, and a standing warning that a dish is a far simpler place than a body.

In vivo describes a process or experiment studied within a living organism, contrasted with laboratory based methods that use isolated cells or tissue.

A type of metastasis in which skin cancer spreads through a lymph vessel and begins to grow more than 2 centimeters away from the primary tumor but before it reaches the nearest lymph node.

An incision is a deliberate surgical cut made through skin and underlying tissue to access the area being treated during an operation.

A surgical procedure in which a portion of a lump or suspicious area is removed for diagnosis.

Inability to control the flow of urine from the bladder (urinary incontinence) or the escape of stool from the rectum (fecal incontinence).

Grown in the laboratory under controlled conditions.