The word "adnion" is a rare term used to describe the point of attachment between two chromatids in a chromosome. Its correct pronunciation is /ˈædniən/ (ad-nee-uhn) with the stress on the first syllable. In this word, the "d" is silent and the vowel sound is "a" as in "cat." The final syllable, "-ion," is pronounced with the stress on the second to last syllable and rhymes with "on." While not commonly used, adnion is an important term in genetics and cell biology.