The word "Acestria" is spelled with an "ae" ligature, which represents the /eɪ/ sound in the word. The "c" is pronounced as an /s/ sound and the following "e" is pronounced as /ɛ/. The "s" is pronounced as a regular /s/ sound and the "t" is pronounced as a /t/ sound. The following "r" is pronounced as /r/ and the final "i" is pronounced as /iː/. In summary, "Acestria" is pronounced as /eɪ.'sɛs.tɹi.ə/.