adjure comes from Latin adiurare ('to swear to, put under oath'), from ad- ('to') + iurare ('to swear'), from ius ('law, oath'), from the Proto-Indo-European root *h₂yew- ('law'). Morphologically, the word is transparent as a compound: its parts remain visible in the modern spelling, while the older history of those parts supplies the deeper ancestry. In modern use, the verb sense is "to charge or command earnestly, often under oath", which keeps the etymology connected to the word's present dictionary value rather than treating it as a merely historical label. The wider word family includes related English forms such as abjure, conjure, perjure, jury and derivatives such as adjuration, adjuratory, showing how the same base continues to support neighboring English vocabulary. The principal historical forms in the chain include Latin adiurare, Latin iurare, which anchor the explanation in named linguistic material.