The hypodiastole (Greekὑποδιαστολή, hypodiastolḗ, lit.'lower separation [mark]'), also known as a diastole,[1] was an interpunct developed in late Ancient and Byzantine Greek texts before the separation of words by spaces was common. In the scriptio continua then used, a group of letters might have separate meanings as a single word or as a pair of words. The papyrological hyphen (enotikon) showed a group of letters should be read together as a single word, and the hypodiastole showed that they should be taken separately. Compare "ὅ,τι" ("whatever") to "ὅτι" ("...that...").[2]

The hypodiastole was similar in appearance to the comma and was eventually entirely conflated with it. In Modern Greek, ypodiastolī́ (υποδιαστολή) refers to the comma in its role as a decimal point, and words such as ό,τι are written with standard commas. A separate Unicode point, ISO/IEC 10646 standard (U+2E12) (⸒), exists for the hypodiastole but is intended only to reproduce its historical occurrence in Greek texts.[2]