IPA: //ˈkwɒdrəmvɪr//
KK: /kwɑːdrəmˌvɪr/
A member of a group of four people who work together for a specific purpose or task.
The quadrumvir was responsible for overseeing the construction of the new public building.
Quadrumvir → It is formed from "quadra-" (from Latin "quattuor", meaning four) and "vir" (meaning man). The term refers to a group of four men, particularly in a political context.
Think of 'four' ('quadra-') men ('vir') working together — that's what a quadrumvir is.
No commonly confused words.