superjacent

You're probably familiar with adjacent, and if you guessed that it's a relative of superjacent, you're right. Both derive from the Latin verb jacēre, meaning "to lie." Adjacent, which is both the more popular and the earlier word (it first appeared in print in the 15th century, while superjacent turned up in the late 16th century), comes from jacēre and the prefix ad-, meaning "near." Superjacent, on the other hand, was formed by combining jacēre with the prefix super-, meaning "over," "above," or "on top of." In case you were wondering, jacēre descendants are also available for other possible configurations: subjacent means "lying below," and circumjacent means "lying near on all sides" or "surrounding."