IPA: /ˌsuːpərɪnˈkʌmbənt/
KK: /sjuːpərɪnˈkʌmbənt/
Describing something that is lying on or above another object, often applying pressure to it.
The superincumbent layer of rock pressed down on the softer layers beneath it.
Superincumbent → It is formed from "super-" (meaning above or over) and "incumbere" (meaning to lie upon). The word describes something that lies over or upon something else.
Think of something that is 'over' ('super-') lying 'upon' ('incumbere') another object — that's why superincumbent means lying over something.
No commonly confused words.