The spelling of the word "acetylise" can be a source of confusion for many. The word is pronounced as /əˈsɛtɪlaɪz/, with the stress on the second syllable. It is spelled with the "yse" ending, which is a common alternative to the more standard "ize" ending, often seen in British English. The word means to add an acetyl group to a molecule or compound, and is commonly used in biochemistry and organic chemistry. The correct spelling is essential in scientific writing where precision is key.