The spelling of the word "Tosiya" can be explained through its phonetic transcription in IPA. The word is pronounced as /ˈtɔːsiə/, with emphasis on the first syllable. The "o" sound is pronounced as a long "aw" sound, and the "si" is pronounced as "see". The "ya" is pronounced as "yah". The spelling of this word may differ in various regions and languages, but the phonetic transcription remains consistent across all dialects.