- preceded by twenty-nine others in a series; 30th
- designating any of the thirty equal parts of something
Origin of thirtiethfrom Middle English thrittythe from Old English thritigotha: see thirty and -th
- the one following the twenty-ninth
- any of the thirty equal parts of something;
in the thirtieth place, rank, group, etc.
- The ordinal number matching the number 30 in a series.
- One of 30 equal parts.
- The ordinal form of the number thirty.
- The person or thing in the thirtieth position.
- One of thirty equal parts of a whole.