What is the X in X-mas?
1560s, from medical Latin diabetes, from late Greek diabetes "excessive discharge of urine" (so named by Aretaeus the Cappadocian, physician of Alexandria, 2c.), literally "a passer-through, siphon," from diabainein "to pass through," from dia- "through" (see dia-) + bainein "to go" (see come).
An old common native name for it was pissing evil. In classical Greek, diabainein meant "to stand or walk with the legs apart," and diabetes meant "a drafting compass," from the position of the legs.
diabetes insipidus diabetes in·sip·i·dus (ĭn-sĭp'ĭ-dəs)
A chronic metabolic disorder characterized by intense thirst and excessive urination, caused by a deficiency of the pituitary hormone vasopressin.
diabetes di·a·be·tes (dī'ə-bē'tĭs, -tēz)
Any of several metabolic disorders marked by excessive discharge of urine and persistent thirst, especially one of the two types of diabetes mellitus.