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di·a·be·tes (dīə-bētĭs, -tēz)
1. Any of a group of diseases characterized by high blood sugar levels caused by insufficient production of insulin, impaired response to insulin, or both, especially:
a. Type 1 diabetes.
b. Type 2 diabetes.
c. Gestational diabetes. In all subsenses also called diabetes mellitus.

[Middle English diabete, from Medieval Latin diabētēs, from Greek, compass, siphon, diabetes, from diabainein, diabē-, to stride or stand with legs apart, cross over, straddle : dia-, dia- + bainein, to go; see gwā- in the Appendix of Indo-European roots.]

Word History: Ancient Greek physicians gave the name diabētēs to a chronic disease characterized by excessive urinationprobably what we now know as diabetes insipidus. (Later, the name was also used for a different disease, diabetes mellitus, in which increased urination is a common symptom.) The term is ultimately derived from the verb diabainein, "to stride or stand with the legs apart, step across, pass over," but it is not certain how diabētēs came to describe the disease. Diabētēs has a variety of other meanings in Greek, including "compass" (since a compass can be likened to a person striding with the legs spread wide) and "siphon" (perhaps because a siphon straddlesso to speaktwo containers and permits the passage of liquid from one to the other). The first known use of diabētēs as a designation for a disease is found in the works of Aretaeus of Cappadocia, who probably lived in the first century AD. Aretaeus's works became standard medical texts of the ancient and medieval world. One chapter of his work On the Causes and Signs of Chronic Diseases is devoted to a condition he calls diabētēs. Aretaeus, however, was not the first physician to give the condition this name, for he offers his own thoughts on the etymology of the term: "The disease seems to me to have acquired the name diabētēs, as if from the Greek word for siphon (diabētēs), because the fluid does not remain in the body." Some modern scholars, on the other hand, have suggested that as a medical term, diabētēs originally made reference to the straddling stance taken during urination by those with the diseasethe intended meaning may have been "one standing with the legs planted firmly apart." Whatever its origin, diabētēs became the standard name for the disease in Greek and medieval medical Latin. Diabetes is first attested in English around 1425 in the spelling diabete, found in a Middle English translation of a Latin medical text by the French physician Guy de Chauliac (ca. 1300-1368): Auicen forsoþ in diabete graunteþ water of whey of shepis mylke. "In the case of diabetes, Avicenna forsooth gives water of the whey of sheep's milk."

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.