Pronunciation: [blˈɔːsta͡ɪn] (IPA) 
Blaustein is a German surname consisting of two parts, "blau" meaning blue and "stein" meaning stone. In IPA phonetic transcription, it is pronounced as /blaʊs.taɪn/. The "au" sound in "blau" is pronounced as a diphthong, with the "a" sound gliding into the "u" sound. The "ei" in "stein" is pronounced as a long "i" sound. Therefore, when spelled out phonetically, the pronunciation of Blaustein is easy to understand.
The word "Blaustein" is of German origin and combines two separate elements: "blau" and "Stein".
1. "Blau" means "blue" in German and is derived from the Old High German word "blāo". This term ultimately traces back to the Proto-Germanic word "blēwaz", which also means "blue".
2. "Stein" translates to "stone" in German and shares its roots with the Old English word "stān" and the Old Norse word "steinn", both meaning "stone". These terms originate from the Proto-Germanic word "stainaz".
Therefore, when combined, "Blaustein" literally means "blue stone" in German.
