The word "bypassings" is spelled with a "y" in the middle because it is derived from the root word "bypass." The "y" represents the sound /aɪ/ which is a diphthong of the vowels /a/ and /i/. This is demonstrated in the IPA phonetic transcription of the word: /baɪˈpæsɪŋz/. The "-ings" at the end of the word signifies the present participle form of the verb, indicating an ongoing action of bypassing. Overall, "bypassings" refers to the act of going around or avoiding something, often used in medical contexts.