The word "gat horn" is a term used to describe a type of trumpet that was popular in medieval times. The spelling of this word can be explained using IPA phonetic transcription, which indicates that the "g" and "h" sounds are pronounced separately. The "g" is pronounced like the "g" in "go," while the "h" is pronounced like the "h" in "house." Therefore, "gat horn" is pronounced as "gat hɔrn." This understanding of the phonetics of this word can help to ensure its proper pronunciation in conversation or academic discussion.