The word "Thonus" is spelled with a "th" sound at the beginning, followed by an "o" sound pronounced like "ah," and then a "nus" ending pronounced like "nuss." The IPA phonetic transcription for this word is /θɑnəs/. The "th" sound is represented by the theta symbol (θ), which is a voiceless dental fricative. The "a" sound in the middle is represented by the alpha symbol (ɑ), which is an open back vowel. The "nus" ending is represented by the combination of the n sound (n) and the schwa sound (ə).