Confusing Sound-Alike Medical Terms

Medical terms can be confusing, especially when some of them sound very similar to other words yet have vastly different meanings. The list below will provide you with some of the more commonly confused pairs along with a brief definition of each. If you have a word set to add, please get in touch to let us know.

Abduct/Adduct

Abduct means to draw and spread away some part of your body parallel to a body or limb.

Adduct means to bring something toward or past the middle part of the body or limb.

Axis/Excess

Axis with regard to anatomy and medical terminology can refer to either the second vertebra of the neck or any of the axial parts of the body.

Excess means an abundance of something. An excess of some quantity is too much, often with a negative connotation. For example, “She has an excessive number of run-on sentences in her transcript.”

Agonist/Antagonist

An agonist refers to a chemical that can combine with a receptive cell and begin some kind of chemical reaction.

An antagonist refers to a substance that acts to limit or decrease the activity of another. In other words, an antagonist substance opposes the specific effects of some drug or chemical.

Anuresis/Enuresis

Anuresis refers to someone’s inability to urinate or the retention of fluids in the bladder.

Enuresis refers to urination, sometimes involuntary. You can remember the difference between the two by associating the “E” in enuresis with elimination.

Apophysis/Epiphysis

Apophysis is a part that is enlarged or sticking out from a body.

Epiphysis refers to bone regeneration, specifically the process of bone ossification that joins it to another bone.

Callus/Callous

A callus is a hardened or thickened part of the skin. (a noun)

Callous refers to the condition of being tough or unfeeling. (an adjective)

Creatine/Creatinine

Creatine is a substance found in the muscles of mammals and is a popular supplement for athletes.

Creatinine is the biological after-product of creatine.

Caudate/Chordate

Caudate refers to the condition of having a tail or something like it.

Chordate describes a group of animals that often have gills.

Chord/Cord

A chord is three or more musical tones played at the same time.

A cord is a rope-like structure, such as an umbilical cord or vocal cords.

Claustrum/Colostrum

Claustrum refers to one of the four areas of the brain called basal ganglia that are located in both hemispheres.

Colostrum is the milk a mother produces after giving birth.

Circumduction/Sursumduction

Circumduction is making a circle with your arms or legs.

Sursumduction is the process of turning or looking upward. You can remember the difference between these easily when you consider the shared root between circumduction and circle.

Cystitome/Cystotome

A cystitome is a cutting device typically used on the gall bladder or urinary bladder. It also refers to a surgical instrument capable of cutting the capsule of a lens.

Cystotome is an instrument used in cystotomy that opens the capsule of a lens during cataract surgery.

Tip: The first has an “I” for incision while the second has the “O” for opening.

Diastasis/Diathesis

Diastasis refers to the process of separation of certain parts of the body that are normally joined together, such as the abdominal muscles or adjacent bones. In physiology, it is the middle of the diastole stage of a heart beat cycle.

Diathesis is a recurrent condition that a patient develops such as in either a hereditary condition or a patient being predisposed to such.

Dyskaryosis/Dyskeratosis

Dyskaryosis is often used as a synonym for dysplasia and refers to an abnormal nuclei in collected cells, usually from the cervix.

Dyskeratosis is the early keratinization of a cell or groups of cells underneath the stratum granulosum.

Dysphagia/Dysphasia

Dysphagia is difficulty swallowing.

Dysphasia refers to an inability to speak or comprehend speech.

Flexor/ Flexure

A flexor is a muscle or limb whose contraction moves another part of the body.

A flexure is the action of bending or curving or the condition of being bent or curved in shape.

Galactorrhea/Galacturia

Galactorrhea refers to a mother’s excessive production of milk or over lactation. Interestingly, this word shares the prefix with the sugar galactose, found in milk, and its suffix is often attached to disorders and diseases as in gonorrhea and diarrhea, with the meaning of “profuse flow” in Greek.

Galacturia refers to the cloudy or milky color of urine.

Humeral/Humoral

Humeral means relating to the humerus bone.

Humoral refers to the bodily fluids. It also has the archaic meaning of referring to the four humors of medieval medicine.

Ileum/Ilium

Ileum a part of the small intestine between the jejunum and the cecum.

Ilium is the large bone that forms each of the pelvis.

Infra- prefix/ Intra-, prefix/Inter- prefix

Infra– means below or within.

Intra– means on the inside or within.

Inter– means between or among.

Malleolus/Malleus

A malleolus is a hammerhead-shaped bone protrusion typically found on the ankles.

The malleus is a small bone in the inner ear that sends vibrations to the incus from the ear drum.

Melanotic/Melenic

Melanotic refers to the presence of melanin or the condition melanosis.

Melenic is darkened color of feces as usually indicates the presence of blood.

Metacarpal/Metatarsal

Metacarpal refers to any of the five bones of the hand.

Metatarsal refers to the bones of the foot (the metatarsus) or the hind limbs of an animal.

Metaphysis/Metastasis

Metaphysis is the slim portion of the long bone containing the growth plate that ossifies (turns to hardened bone) between the diaphysis and the epiphyses.

Metastasis is the development of secondary malignant growths away from a primary cancer.

Mucous/Mucus

Mucous resembling or consisting of mucous, such as that discharged from the nose. Also refers to the consistency of a substance. This word is often used adjectivally.

Mucus is the actual substance itself, often slimy in consistency and colloquially referred to as “snot.”

Pancreas/Pancrease

The pancreas is a large organ near that stomach that releases digestive enzymes into the duodenum.

Pancrease are chemicals containing digestive enzymes.

PONS/pons 

PONS is an acronym that refers to a test called the Profile of Nonverbal Sensitivity.

The pons is a collection of nerve fibers in the brain stem below the cerebellum and behind the medulla oblongata.

Peritoneal/Peroneal

Peritoneal refers to the lining of the abdominal cavity.

Peroneal refers to the outer side of the calf on your leg.

Perfuse/Profuse

Perfuse means to supply an organ with blood or a blood substitute by pushing it through blood vessels or other natural means.

Profuse has the quality of excess or abundance and is found in medical phrases such as “profuse sweating,” which refers to a condition of excessive sweat production typically as the result of some disease.

Radical/Radicle

In medicine, a radical removes the root of all disease or diseased tissue.

A radicle is a subdivision of a vein that has a rootlike appearance.

Scatoma/Scotoma
Scatoma is a tumor-like mass composed of feces

Scotoma refers to a partial loss of vision or a blind spot in an otherwise normal field of vision.

Super – a prefix/Supra-, a prefix

Super– has the quality of being above or over something else.

Supra– has the quality of being beyond the limit or outside of something else.

Both words share the quality of being above or over.

Tendon/ Tenon capsule

A tendon is a flexible cord that connects a muscle to a bone.

Tenon refers to the process of joining two objects together in a secure manner.

Trichocyst/Trichosis

Trichocyst are small complex organelles.

Trichosis refers to an abnormality or disease of the hair follicle.

Vesical/Vesicle

Vesical is something related to or impacting the urinary bladder.

Vesicle is a fluid or air-filled cavity or sac.

Villous/Villus

Villous refers to a structure covered with villi, such as the epithelium.

Villus are minute projections that help with absorption of substances. Commonly found in the small intestine as well as in the maternal amniotic sac.

Viscous/Viscus

Viscous describes a thick sticky substance.

Viscus (plural, viscera) is an internal organ of the body.

When in doubt about the right word to choose, it’s always best to verify terms and ask for help whenever needed. As a professional legal transcriptionist, each of us wants to prepare transcripts as free from error as humanly possible. When we work as a team, we are better equipped to do just that. If you have suggestions for tricky medical word pairs to add to our list, please let us know.