Origin of thirteenMiddle English thrittene from Old English threotyne: see three and -teen
- The cardinal number that is equal to the sum of 12 + 1.
- The 13th in a set or sequence.
- Something having 13 parts, units, or members.
Origin of thirteenMiddle English thyrtene alteration of thrittene from Old English thrēotīne ; see trei- in Indo-European roots.
- Ordinal: thirteenth
From Middle English thirttene, variant (through metathesis) of thrittene, from Old English Ã¾reotÄ«ene, Ã¾reotene, from Proto-Germanic *Ã¾ritehun. Compare West Frisian trettjin, Dutch dertien, German dreizehn, Danish tretten.