fifteenth
UK: ˌfɪfˈtiːnθ | US: ˌfɪfˈtiːnθ
adj. coming after the fourteenth in a series; 15th
n. the position or rank of number 15 in a sequence
The word "fifteenth" combines "fifteen," derived from Old English "fīftīene" (from "fīf" meaning "five" + "tīene" meaning "ten"), with the ordinal suffix "-th," used to form sequence numbers. This follows the Germanic pattern of constructing cardinal numbers (e.g., "five-ten") and adding "-th" to denote order (e.g., "third," "tenth"). The suffix "-th" traces back to Proto-Germanic *-dô and is related to Latin "-tus."
Her birthday is on the fifteenth of March.
He finished in fifteenth place in the race.
The fifteenth chapter of the book is the most exciting.
This is the fifteenth time I’ve called you today.
The festival runs from the tenth to the fifteenth of July.