The word "aidest" is spelled in Middle English and is pronounced /ˈeɪdɪst/. It is derived from the Old English verb "ādian" which means "to help, support, or assist." The spelling of the word reflects the pronunciation of the long "a" sound followed by "-d" and "-est" suffix. The word is an archaic form of the second-person singular present indicative form of the verb "aid", which means to give assistance or support.