Vainu (Vain)

Grassplot, village green or common. First known as Olga / Ольгинская ул. until 1925 (probably unrelated to the earlier name of Pebre, 10 km away), then switched – for reasons of consonance? Olga > Anger – to Angerstraße (village green or common) / Лужаечная ул. (lawn) in 1926, then back to Vainu in 1937. Renamed 1940-1941 as Mõrra. Vain is also a family name and I recommend Peep Vain’s The Most Important Question, from your local bookstore.