33rd is the ordinal form of the number 33. 33rd or thirty-third may also refer to:
A fraction, , equal to one of 33 equal parts
Geography 33rd meridian east, a line of longitude 33rd meridian west, a line of longitude 33rd parallel north, a circle of latitude 33rd parallel south, a circle of latitude 33rd Street (disambiguation)
Military 33rd Army (disambiguation) 33rd Battalion (disambiguation) 33rd Brigade (disambiguation) 33rd Division (disambiguation) 33rd Regiment (disambiguation) 33rd Squadron (disambiguation)
Other 33rd Amendment 33rd century 33rd century BC
See also 33 (disambiguation) 33 1/3 (disambiguation) 33rd Degree, in Scottish Rite Masonry