| Term | Definition |
| a- or an- | A- or an- means no, or without.
For example, asepsis means without pathogens, or the state of being free from pathogens. |
| ab- | Ab- means away from.
For example, abduction is movement of a limb away from the midline of the body. |
| ad- | Ad- means toward.
For example, adduction is movement of a limb toward the midline of the body. |
| aut(o)- | Aut- means self.
Aut(o) is its combining form.
For example, an autograft is a surgery using one’s own skin to make the repair. |
| brady- | Brady- means slow.
For example, bradycardia refers to a slow heartbeat |
| chem(o)- | Chem- means chemistry or drug.
Chem(o) is its combining form.
For example, chemotherapy is a drug treatment used to treat cancer. |
| dia- | Dia- means complete or through.
For example, diagnosis refers to a complete state of knowledge for the purposes of identifying a disease. |
| dis- | Dis- means to separate or take apart.
For example, dissection refers to cutting open an organism to observe its internal structures.
Dis- can also be used to mean:
lack, as in distrust or disorientation
reversal, as in disconnect |
| dys- | Dys- means abnormal or painful.
For example, dysentery is the name of a disease that causes inflammation of the intestine, and is quite painful. |
| endo- | Endo- means inside or within.
For example, endoscopy is a method of visualizing internal organs with a camera. |
| epi-/exo- | Epi- and exo- both mean outside or outside of.
For example, epicardium is the outer heart tissue, and exoskeleton is a skeletal structure found on the outside of an organism |
| eu- | Eu- means good or normal.
For example, euglycemia refers to a normal level of blood sugar. |
| hyper- | Hyper- means above or above normal.
For example, hypertension refers to high blood pressure. |
| hypo- | Hypo- means under or below normal.
For example, hypoglycemia refers to low blood sugar. |
| inter- | Inter- means between or among.
For example, intercellular means between or among cells |
| lyso- | Lyso- means dissolve or dissolution.
For example, lysosomes are parts of cells that dissolve or break down waste. |
| macro- | Macro- means large.
For example, macrophages are large cells. |
| mal- | Mal- means bad or ill.
For example, malignant refers to a growth that is cancerous, made up of abnormal cells multiplying uncontrollably. |
| micro- | Micro- means small.
For example, a microscope is a tool used by scientists to view small body parts, such as tissues and cells. |
| mono- | Mono- means single or one.
For example, a monolayer refers to a structure with only one layer. |
| neo- | Neo- means new.
For example, a neonate is a newborn. |
| para- | Para- means beside, beyond, around, or abnormal.
For example, parathyroid glands are small glands next to, or beside, the thyroid |
| poly- | Poly- means many, or more than usual.
For example, polydipsia means excessive thirst, where dipsa is a Greek root word meaning thirst. |
| post- | Post- means after or behind.
For example, postmortem means after death |
| pre- | Pre- means before.
For example, preoperative means before an operation. |
| pro- | Pro- means before.
For example, prognosis means a prediction of the course of a disease, based on medical knowledge, before it happens. |
| re- | Re- means again or backward.
For example, relapse refers to a recurrence of a past condition. |
| schiz(o)- | Schiz means split.
Schiz(o) is the combining form.
For example, schizophrenia refers to a mental disorder in which mental functions become split and confused. |
| sub- | Sub- means below or under.
For example, subcutaneous refers to something below the skin. |
| supra- | Supra- means above or excessive.
For example, suprapatellar refers to the area above the patella or kneecap. |
| tachy- | Tachy- means fast.
For example, tachycardia is a fast heartbeat. |
| trans- | Trans- means moving through or across.
For example, transfusion is a transfer of blood from one person to another. |
