circumfix

[ sur-kuh m-fiks ]
/ ˈsɜr kəmˌfɪks /
Grammar

noun

a prefix and a suffix attached to a root or stem, as the a and -ing in a-going.

verb (used with object)

to add a circumfix to.
Related formscir·cum·fix·a·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019