including ordinal numerals, are grouped into a separate part of speech (, hence, "noun numeral" in older English grammar books). However, in modern interpretations of English grammar, ordinal numerals are usually considered adjectives.

Ordinal numbers may be written in English with numerals and letter suffixes: 1st, 2nd or 2d, 3rd or 3d, 4th, 11th, 21st, 101st, 477th, etc., with the suffix acting as an ordinal indicator.