The word "Acervative" is spelled with a "c" rather than a "k" because it is derived from the Latin word "acervare", meaning to accumulate or gather. The correct pronunciation is [əˈsɜːr.və.tɪv], with emphasis on the second syllable. The "a" is pronounced as "uh" and the "e" is silent. This uncommon word refers to a substance that prevents spoilage or decay, especially in food. Its use is not very common, but it is still worth knowing how to spell and pronounce it correctly.