The word "Borthwick" is spelled using the English alphabet and its pronunciation is transcribed in IPA as /ˈbɔːθɪk/. This word is derived from the name of a parish in Scotland, and it is commonly used as a surname. The "b" in "Borthwick" is pronounced as /b/ and the "th" is pronounced as /θ/, which is a voiceless dental fricative sound. The "wick" part is pronounced as /wɪk/ and it rhymes with "Nick". Overall, the spelling of "Borthwick" is phonetically irregular, but it follows a consistent pattern of English spelling conventions.
The word "Borthwick" is actually a surname rather than a common word. It is of Scottish origin and is believed to be derived from a place name. The surname Borthwick is associated with the Borthwick Castle, which is located in the Scottish Borders region. The castle and the surname are thought to have originated from the Old English words "borth" meaning "fortification" and "wic" meaning "dwelling" or "farm". Over time, the spelling and pronunciation may have evolved, but the etymology traces back to the place name.