- a combining form representing sacrum in compound words: sacroiliac.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for sacro-
word-forming element meaning "of or involving the sacrum, the bone at the base of the spine. E.g. sacro-iliac.
Online Etymology Dictionary, © 2010 Douglas Harper