Fifteenth or 15th may refer to:
Ordinal form of the number 15 (number) A fraction, , equal to one of 15 equal parts "The 15th", a 1979 song by Wire Fifteenth of the month, a recurring calendar date Fifteenth (interval)
Geography 15th meridian east, a line of longitude 15th meridian west, a line of longitude 15th parallel north, a circle of latitude 15th parallel south, a circle of latitude 15th Avenue 15th district (disambiguation) 15th Street (disambiguation)
Military Fifteenth Army (disambiguation) 15th Division (disambiguation) 15th Regiment (disambiguation) 15th Squadron (disambiguation)
History Fifteenth (tax), medieval English tax Fifteenth Amendment (disambiguation) Fifteenth Amendment to the United States Constitution 15th century 15th century BC
See also 15 (disambiguation)