Where does “Østhammar” come from?

Østhammar (Old Swedish) comes from Old Swedish hamar, from Old Norse hamarr, from Proto-Germanic hamaraz, from Proto-Indo-European h₂eḱmoros, from Proto-Indo-European h₂éḱmō, from Proto-Indo-European h₂eḱ- — sharp.

Ancestry of “Østhammar”, step by step

Østhammar traces back through two separate lines of ancestry.

via Old Swedish hamar

StepLanguageWordMeaning
1Old Swedishhamarhammer; mountain height, outcrop
2Old Norsehamarrstone; a steep cliff, crag, a rock face; hammer
3Proto-Germanichamarazhammer
4Proto-Indo-Europeanh₂eḱmoros
5Proto-Indo-Europeanh₂éḱmōstone
6Proto-Indo-Europeanh₂eḱ-sharp

via Danish øster

StepLanguageWordMeaning
1Danishøster
2Old Norseaustreast
3Proto-Germanicaustrąeast; east, eastward
4Proto-Germanicaustrazeast, eastern
5Proto-Indo-European*h₂éwsterosin the direction of dawn, east
Every word from Proto-Indo-European h₂eḱ-Every word from Proto-Indo-European h₂éḱmōEvery word from Proto-Indo-European h₂eḱmoros