Where does “просторно” come from?

просторно (Russian) comes from Russian просто́рный, from Proto-Slavic *prostorьnъ — vast, spacious.

просторно (Russian): spaciously; loosely, in a loose-fitting manner;...

Definitions

  1. spaciously; loosely, in a loose-fitting manner;...

Ancestry of “просторно”, step by step

StepLanguageWordMeaning
1Russianпросто́рныйspacious, roomy
2Proto-Slavic*prostorьnъvast, spacious
Every word from Proto-Slavic *prostorьnъEvery word from Russian просто́рный