The spelling of the word "Antalkaline" can be a bit confusing. The correct pronunciation is /æntælˈkælɪn/. The prefix "anti" means against or opposite, while "alkaline" refers to the pH level of a solution. So, antalkaline refers to a substance that is acidic or neutral, as opposed to alkaline. For example, lemon juice is antalkaline because it has a low pH level. Although it may be a tongue-twister, the spelling and pronunciation of antalkaline make sense once you break it down phonetically.
Reducing or neutralizing alkalinity.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.