The spelling of the word "acted as middle" can be explained through the International Phonetic Alphabet (IPA). The first sound, /æ/, is a short "a" sound, followed by /k/ and /t/, which represent the "k" and "t" sounds respectively. The next sound, /ɪd/, represents the past tense ending "-ed." The final part, /æz/ is pronounced as "az," representing the "as" sound. Together, these sounds create the word "acted as middle," which means someone who played the role of a mediator or intermediary between two parties.