Unlike cardinal numerals, which function simply as attributes defining a numeric value (four houses), ordinal numerals identify the numeric position a given member of a set occupies relative to other members of the same set (the fourth house). The morphological relationship between ordinal and cardinal numerals serves as a parameter by which languages can be categorized. This relationship may be dependent (the ordinal regularily derived from the root of the corresponding cardinal) or independent (suppletive root or/and irregular derivation). Examination of only the first three to five numerals is generally required to assign a given language a value within this parameter.[1] There is no overlap between values; each language falls clearly and exclusively into one type.

Types:

NoOrd: Ordinal numerals do not exist in the language; this function is fulfilled by adverbial structures.

OTTh: Ordinal and cardinals numerals have the same form and are only distinguishable by word order, contextual cues, or pragmatic considerations. This is also known as the “one, two, three” type.

FTTh: Only the number ‘one’ has a uniquely ordinal (suppletive) form. This is also known as the “first, two, three” type.

OthTthThth: Each ordinal is derived, through the same pattern, from the root of its corresponding cardinal numeral. This is also known as the “oneth, twoth, threeth” type.

Oth~FTthThth: Each ordinal numeral is derived, through the same pattern, from the root of the corresponding cardinal numeral, with the exception of the numeral ‘first,’ for which both a derived and suppletive form exists. This is also known as the “first/oneth, twoth, threeth” type.

FTthThth: Each ordinal numeral is derived, through the same pattern, from the root of the corresponding cardinal numeral, with the exception of the numeral ‘first,’ whose form is suppletive. This is also known as the “first, twoth, threeth” type.

FSThth: Each ordinal numeral is derived, through the same pattern, from the root of the corresponding cardinal numeral, with the exception of numerals expressing small values. Prototypically, this is limited to ‘first’ and ‘second,’ but can in some cases extend beyond these two. [2] This is also known as the “first, second, threeth” type.

Mix: Ordinal numerals are formed using a system not listed above. Languages in this category may use any of a variety of strategies; for example, the use of suppletive forms for numerals between 4 and 9, and the derivation of ordinals from corresponding cardinals for small numerals.

[1] Compound numerals above 10 or 20 are not considered for this parameter. Some follow the same pattern of formation as their components, while others do not. Compare the English twenty-one and twenty-first to the Hungarian első and huszonegyedik.

[2] For example, see English: first, second, third, fourth, fifth, etc.