Where does “остър ъгъл” come from?

остър ъгъл (Bulgarian) comes from Bulgarian ъгъл, from Proto-Slavic ǫgъlъ, from Proto-Balto-Slavic *ángulas, from Proto-Indo-European h₂engulos, from Proto-Indo-European h₂eng- — curve, bend.

остър ъгъл (Bulgarian): acute angle an angle of under 90 degrees

Definitions

  1. acute angle an angle of under 90 degrees

Ancestry of “остър ъгъл”, step by step

остър ъгъл traces back through two separate lines of ancestry.

via Bulgarian ъгъл

StepLanguageWordMeaning
1Bulgarianъгълangle, corner
2Proto-Slavicǫgъlъcorner, angle
3Proto-Balto-Slavic*ángulas—
4Proto-Indo-Europeanh₂engulosjoint?
5Proto-Indo-Europeanh₂eng-curve, bend

via Bulgarian о́стър

StepLanguageWordMeaning
1Bulgarianо́стърsharp
2Proto-Slavicostrъsharp
3Proto-Balto-Slavicaśrassharp
4Proto-Indo-European*h₂eḱróssharp
5Proto-Indo-Europeanh₂eḱ-sharp
Every word from Proto-Indo-European h₂eng- →Every word from Proto-Indo-European h₂engulos →Every word from Proto-Balto-Slavic *ángulas →