A female Deltan navigator who briefly served aboard the refit U.S.S. Enterprise in 2271 under James Kirk. She had once had a romantic relationship with Cmdr. Will Decker, but as a Deltan her oath of celibacy had already been filed before working among other species. Ilia was killed when the V'ger entity stored her as a memory for use as a probe-drone later, even though its intact memories still held feelings for Decker.