However, historical linguistics seeks to explain how they came to be so and distinguishes different kinds of irregularity according to their origins.
Most irregular paradigms (like man:men) can be explained by phonological developments that affected one form of a word but not another (in this case, Germanic umlaut).
Historical linguistics uses the term "suppletion"[1] to distinguish irregularities like person:people or cow:cattle that cannot be so explained because the parts of the paradigm have not evolved out of a single form.
Hermann Osthoff coined the term "suppletion" in German in an 1899 study of the phenomenon in Indo-European languages.
For example, in Georgian, the paradigm for the verb "to come" is composed of four different roots (di-, -val-, -vid-, and -sul-; მი-, -ვალ-, -ვიდ-, -სულ-).
[6] Similarly, in Modern Standard Arabic, the verb jāʾ ('come') usually uses the form taʿāl for its imperative, and the plural of marʾah ('woman') is nisāʾ.
In Romansh, Rumantsch Grischun substitutes present and subjunctive forms of ir with vom and giaja (both are from Latin vādere and īre, respectively) in the place of mon and mondi in Sursilvan.
'what one clings to' cognate to Sanskrit: bhadra "fortunate" from Old Latin: duenos from Proto-Indo-European: *meh₂- "ripen", "mature" from Proto-Indo-European: *wers- "peak" Old Church Slavonic: лоучии "more suitable, appropriate"[13] The comparison of "good" is also suppletive in Estonian: hea → parem → parim and Finnish: hyvä → parempi → paras.
A few examples, listed by principal parts: In Bulgarian, the word човек, chovek ("man", "human being") is suppletive.
For example, двама, трима души, dvama, trima dushi ("two, three people"); this form has no singular either.
(A related but different noun is the plural души, dushi, singular душа, dusha ("soul"), both with accent on the last syllable.)
[23] This is because *あらない, the hypothetically regular negative form of ある, is not used either, and is simply replaced with ない.
A few examples, listed by principal parts: In some Slavic languages, a few verbs have imperfective and perfective forms arising from different roots.
In any case, in modern usage, it has been replaced by люди, lyudi, the singular form of which is known in Russian only as a component of compound words (such as простолюдин, prostolyudin).
This suppletion also exists in Polish (człowiek > ludzie), Czech (člověk > lidé), Serbo-Croatian (čovjek > ljudi),[25] Slovene (človek > ljudje), and Macedonian (човек (čovek) > луѓе (lugje)).
Strictly speaking, suppletion occurs when different inflections of a lexeme (i.e., with the same lexical category) have etymologically unrelated stems.
The pairs are distantly etymologically related, but the words are not from a single Modern English stem.