The term 'SACRO ADDITION' is a combination of two words, 'sacro' and 'ADDITION'. 'Sacro' is derived from the Latin word for 'SACRED', while 'ADDITION' refers to the act of adding something. The crossword solution for this term is 'iliac', which is an anatomical term referring to the region of the lower abdomen near the hip bone. This area is often referred to as the 'sacroiliac joint', as it is where the sacrum (the triangular bone at the base of the spine) connects with the ilium (the uppermost part of the hip bone).