circum-

from The Century Dictionary.

• noun A prefix of Latin origin, meaning ‘round about,’ ‘in a circle,’ ‘on all sides’: frequent in compounds taken from the Latin, or formed in English or other modern tongues. Many such compounds are merely occasional. Only the principal ones are entered in this dictionary.

from the GNU version of the Collaborative International Dictionary of English.

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

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• prefix around