The Proto-Indo-European word *k̂el-
Word *k̂el-
Meaning warm, cold
Synonyms *gʷhermos, *gel-, *tep-, *h₃eug-, *srīges-, *gʷhrensós

Comments
Ltv. silt, Lith. šilti, Ir. clithe/, Welsh clyd, ON hlǽr, Eng. hlēow/lukewarm, Gm. lāo/lau, Skr. śiśira, Av. sarəta, Osset. sald, Pers. /sard, Lat. calēre, Kurd. šíle/kul/germ