Proto-Indo-European numerals

The numerals and derived numbers of the Proto-Indo-European language (PIE) have been reconstructed by modern linguists based on similarities found across all Indo-European languages. The following article lists and discusses their hypothesized forms.

The cardinal numbers are reconstructed as follows:

Other reconstructions typically differ only slightly from Beekes and Sihler. A nineteenth century reconstruction (by Brugmann) for thousand is *tūsḱmtiə. See also Fortson 2004.

The elements *-dḱomt- (in the numerals "twenty" to "ninety") and *dḱm̥t- (in "hundred") are reconstructed on the assumption that these numerals are derivatives of *deḱm̥(t) "ten".

Lehmann believes that the numbers greater than ten were constructed separately in the dialects groups and that *ḱm̥tóm originally meant "a large number" rather than specifically "one hundred."

The numbers three and four had feminine forms with the suffix *-s(o)r-, reconstructed as *t(r)i-sr- and *kʷetwr̥-sr-, respectively.

Special forms of the numerals were used as prefixes, usually to form bahuvrihis (like five-fingered in English):

The ordinal numbers are difficult to reconstruct due to their variety in the daughter languages. The following reconstructions are tentative:

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