From Hebrew kol, meaning 'voice' or 'sound,' though also used as a short modern name in English contexts.
Kol has deep Norse and Old English roots: the Old Norse *Kolr* referred to someone dark-haired or swarthy, related to the word for coal, and appears throughout the medieval Icelandic sagas as a byname and given name. The name is closely related to Cole and Colin in the English tradition, and to Nikolaj and Klaus through their shared Greek ancestor Nikolaos.
In Scandinavia, Kol appears in runic inscriptions and land records from the Viking Age, marking it as one of the most ancient single-syllable names still recognizable in the modern world. Separately, in Hebrew, *kol* (קוֹל) means voice or sound — a word of enormous theological and poetic weight in Jewish tradition. 'A still, small voice' — *kol demamah dakah* — is the form in which the divine speaks to Elijah in the Book of Kings, and the word echoes through liturgy and scripture in ways that give the name a contemplative, resonant dimension quite apart from its Norse lineage.
In contemporary usage, Kol has been boosted by the character Kol Mikaelson in the television series *The Originals* and *The Vampire Diaries*, where it portrayed a charismatic, dangerous original vampire — lending the name a certain dark magnetism. But stripped of pop culture association, Kol stands on its own as a name of admirable economy: one syllable, ancient pedigree, instantly memorable.