érus

érus is a Cyrillic letter. It is the tenth letter of the Bulgarian alphabet and the eleventh letter of the Serbian and Macedonian alphabets. In all these alphabets, it is pronounced as /r/. The letter ⟨r⟩ is derived from the Greek letter Rho (Ρ, ρ). The name of the letter in Church Slavonic is "Rtsy" (ръци), meaning "speak".

In Old Church Slavonic, the letter ⟨r⟩ was used to represent the sound /r/. It was also used in some other Slavic languages, such as Russian and Ukrainian, before they developed their own distinct alphabets. The letter ⟨r⟩ has been used in the Cyrillic alphabet since its creation in the 9th century. It has remained virtually unchanged in form and sound throughout the centuries.

The letter ⟨r⟩ is used in many words in Slavic languages. For example, in Russian, it is used in words such as "рука" (ruka, hand) and "река" (reka, river). In Serbian, it is used in words such as "радост" (radost, joy) and "риба" (riba, fish). In Macedonian, it is used in words such as "работа" (rabota, work) and "ритам" (ritam, rhythm). The letter ⟨r⟩ is also used in some non-Slavic languages that use the Cyrillic alphabet, such as Kazakh and Kyrgyz.