Pronunciation IPA (key): /ˈhaɪ.ə.rɑː(r).ki/ or /ˈhaɪ.rɑː(r).ki/ Audio (US)(file) Noun Singular hierarchy Plural hierarchies A hierarchy is a body of officials organized in ranks so that each is above or below another. Any group of objects ranked so that every one is above or below another.Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads