The spelling of "fauntleroy" is a bit unusual, but it can be explained using the International Phonetic Alphabet (IPA). The first syllable sounds like "fawn", with a long "awn" sound. The second syllable sounds like "tler", with the "t" and "l" sounds blended together. The third syllable is pronounced like "oi", with a diphthong that starts with the "o" sound and transitions into the "i" sound. The final syllable is "oy", which rhymes with "boy". Together, the pronunciation is "Fawn-tler-oy".
The word "Fauntleroy" is derived from a fictional character named Cedric Errol, who appears in the 1886 novel called "Little Lord Fauntleroy" written by Frances Hodgson Burnett. In the story, Cedric is a young boy from New York who becomes an English nobleman. His noble title is "Lord Fauntleroy", and the name became associated with a particular fashion style for boys. The term "Fauntleroy" eventually entered the English language as a noun that refers to a young boy who is dressed in formal, fancy, or excessively preppy clothing.