Circum-

·- A Latin preposition, used as a prefix in many English words, and signifying around or about.

circum
circum [properly acc. from circus = κίρκος], adv. and prep., designates either an entire encompass...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
circum
circum (1) I acc.of circus, adv.and praep. I I. Adv, around, round about, all around : Arboribus ...

An Elementary Latin Dictionary