U+1F99 "ᾙ" Greek Capital Letter Eta with Dasia and Prosgegrammeni Unicode Character

U+1F99 "ᾙ" Greek Capital Letter Eta with Dasia and Prosgegrammeni is a historical polytonic Greek letter that combines a capital Eta (Η) with a dasia, which is a rough breathing mark indicating an initial "h" sound, and a prosgegrammeni, a small iota subscript written alongside the letter instead of beneath it, typically used in ancient Greek orthography for certain grammatical forms such as the dative case. This character appears in classical and liturgical texts where precise accentuation and spiritus asper breathing are preserved, and it is part of the Greek Extended Unicode block, which supports the complex diacritic system of ancient Greek writing.