The spelling of the name "Thurstain" can be a bit tricky due to its pronunciation. Using the International Phonetic Alphabet (IPA) transcription, it can be broken down into: /ˈθɜːrsteɪn/. The "th" sound is pronounced as in "thing," the vowel in the first syllable is pronounced as in "fern," and the "ain" ending is pronounced as in "cane." Overall, the spelling is a reflection of the Old Norse origin of the name, as it was often spelled with a "þ" (thorn) instead of a regular "t."
The name Thurstain is of Old Norse origin. It is derived from the combination of two elements: þor meaning thunder (referring to the Norse god Thor) and steinn meaning stone or rock. Therefore, Thurstain can be translated as thunder stone or rock of Thor.