Pronunciation: (yer),[key] —n. 1. Slavic Ling.either of two letters (ъ, ь) of the Cyrillic alphabet used, as in Old Church Slavonic, to indicate two short vowels, or, as in Russian, to indicate that the preceding consonant is hard or soft. Cf. hard sign, soft sign. 2. either of the short, lax vowels of Old Church Slavonic represented by these signs, front jer (ъ, usually transcribed as i) and back jer (ь, usually transcribed as ŭ).