有叱 (*Is-)
This form is attested a total of sixty-two times across four out of the five known brush-written interpretative gugyeol glosses to the Buddhist canon, composed between the tenth and thirteenth centuries.
In Old Korean orthography, native terms with clear Chinese equivalents are usually written with an initial Chinese character (logogram) glossing the meaning of the word, followed by one or more Chinese characters (phonograms) that transcribe the final syllable or coda consonant of the term. In the case of 有叱, the first character shows that this is the native Old Korean word for “to be; to have”, and the subsequent character(s) show(s) that the coda consonant of this word is *-s. Because the semantics and the final phoneme(s) match, the word is conventionally reconstructed as *Is-, the ancestor of Middle Korean 잇다 (Yale: ista). Note that the reconstruction was not necessarily the actual pronunciation. Rather, it should simply be considered as a method of representing an Old Korean form phonetically by using its Middle Korean reflex.
According to scholarly convention, the elements of the reconstruction which are not directly represented by phonograms are given in capital letters. This allows readers to identify what part of the reconstruction is attested and what part is applied retroactively from the Middle Korean reflex. The accuracy of the reconstruction *Is- is supported by the Jilin leishi, a twelfth-century wordlist of Korean terms as transcribed by a Chinese visitor. The Leishi writes the Old Korean word for Chinese 有 (“being; having”) as 移室 or 移實. The sequences are reconstructed in Late Middle Chinese as roughly */ji ʂiɪt/. As the */-ɪt/ ending is believed to transcribe the Old Korean nominalizer 尸 (-l), the Old Korean verb stem for "to be; to have" must have been pronounced similar to */jiʂi-/.