kelə-, Proto-Indo-European root meaning "warm." It forms all or part of: caldera; calid; Calor; caloric; calorie; calorimeter; cauldron; caudle; chafe; chauffeur; chowder; coddle; lee; lukewarm; nonchalant; scald (v.) "afflict painfully with hot liquid or steam."

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit carad- "harvest," literally "hot time;" Latin calor "heat," calidus "warm," calere "be hot;" Lithuanian šilti "become warm," šilus "August;" Old Norse hlær, Old English hleow "warm."

Proto-Indo-European root meaning "to hold."

It forms all or part of: Antioch; asseverate; asthenia; asthenosphere; cachectic; cachexia; calisthenics; cathexis; entelechy; eunuch; epoch; hectic; Hector; ischemia; myasthenia; neurasthenia; Ophiuchus; persevere; schema; schematic; scheme; scholar; scholastic; school (n.1) "place of instruction;" severe; severity; Siegfried.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit sahate "he masters, overcomes," sahah "power, victory;" Avestan hazah "power, victory;" Greek skhema "figure, appearance, the nature of a thing," related to skhein "to get," ekhein "to have, hold; be in a given state or condition;" Gothic sigis, Old High German sigu, Old Norse sigr, Old English sige "victory."