kari conjugation
A classical Japanese adjective inflection pattern formed by attaching the classical existential verb あり (modern ある) to the adverbial 〜く form, yielding forms like 〜かり, 〜かった, 〜かろう. This pattern is the historical source of modern i-adjective inflections such as 〜かった and 〜かろう. The term is used in Japanese grammar education and linguistic descriptions of classical Japanese.
Modern なかった derives from the classical kari conjugation.
The kari conjugation is an inflection formed by attaching あり to the adverbial く form of adjectives.