IPA: /ˈsuːpəˌklʌstə/
KK: /ˈsuːpərˌklʌstər/
A large group of galaxy clusters that are close to each other in space and are held together by gravity.
The supercluster contains thousands of galaxies and spans millions of light-years.
Supercluster → It is formed from "super-" (meaning above or beyond) and "cluster" (from Old English "clyster", meaning a group or bunch). The word "supercluster" refers to a large group of galaxies that are bound together by gravity, thus being a cluster that is above or beyond typical clusters.
Think of 'super-' meaning 'above' and 'cluster' as a 'group' — a supercluster is a group of galaxies that is larger than typical clusters.
No commonly confused words.