31st

31st is the ordinal form of the number 31. 31st or Thirty-first may also refer to:

• A fraction, 1⁄31, equal to one of 31 equal parts
• 31st of the month, a recurring calendar date

Geography

• 31st meridian east, a line of longitude
• 31st meridian west, a line of longitude
• 31st parallel north, a circle of latitude
• 31st parallel south, a circle of latitude
• 31st Street (disambiguation)

Military

• 31st Army (disambiguation)
• 31st Battalion (disambiguation)
• 31st Brigade (disambiguation)
• 31st Division (disambiguation)
• 31st Regiment (disambiguation)
• 31st Squadron (disambiguation)

Other

• 31st Amendment
• 31st century
• 31st century BC

See also

• 31 (disambiguation)
• The Thirty-First of February, 1949, American fantasy story collection