Unsure. The status of Proto-Indo-European *kerh₃- (“heat”, “fire”, also “to burn”) is uncertain. Probably related to Old English heorþ (“hearth”), Old Norse hyrr (“fire”), Gothic 𐌷𐌰𐌿𐍂𐌹 (hauri, “coal”), Old High German harsta (“roasting”), Russian курить (kuritʹ, “to smoke, burn, fumigate”) and церен (ceren, “brazier”), Old Church Slavonic курити (kuriti, “to smoke”) and крада (krada, “hearth, fireplace”), Lithuanian kurti̇̀ (“to heat”), karštas (“hot”) and krosnis (“oven”), Sanskrit कृष्ण (kṛṣṇa, “burnt, black”) and कूडयति (kūḍayati, “singes”), and maybe Latin cremāre (“to burn”).