thirteenth
UK: ˌθɜːˈtiːnθ | US: ˌθɜːrˈtiːnθ
adj. coming after the twelfth in a series; 13th in order.
n. the ordinal number matching the number 13 in a sequence.
The word "thirteenth" combines "thirteen," derived from Old English "þrēotīene" (where "þrēo" means "three" and "tīene" means "ten"), with the ordinal suffix "-th," which transforms cardinal numbers into ordinal numbers (e.g., "four" → "fourth"). This structure follows the Germanic pattern of forming ordinals by adding "-th" to the cardinal form. The "-th" suffix traces back to Proto-Germanic *-dô and Proto-Indo-European *-tos, marking order or sequence.
Her birthday falls on the thirteenth of June.
He was the thirteenth person to arrive at the meeting.
The thirteenth chapter of the book is particularly intriguing.
They celebrated their thirteenth anniversary last week.
The thirteenth floor is often omitted in buildings due to superstition.