Il"i*ac (?), a. [L. Iliacus, Gr. &?;. See Iliad.] Pertaining to ancient Ilium, or Troy. Gladstone.

Il"i*ac, a. [Cf. F. iliaque. See Ileum, and cf. Jade a stone.] 1. (Anat.) Pertaining to, or in the region of, the ilium, or dorsal bone of the pelvis; as, the iliac artery. [Written also ileac.]

2. See Ileac, 1. [R.]

Iliac crest, the upper margin of the ilium. -- Iliac passion. See Ileus. -- Iliac region, a region of the abdomen, on either side of the hypogastric regions, and below the lumbar regions.