Starfleet Rank
Species Founder Changeling
Planet Discovered ca. 2337 in Denorious Belt, Bajoran system
Affiliation Bajoran Militia
Gender Male
Portrayed Rene Auberjonois

Found adrift and alone in the Denorious Belt in his natural gelatinous state with no clue to his origin, this unique shapeshifter was returned to Cardassian-occupied Bajor in 2356 and given to Dr. Mora Pol at the Bajoran Institute for Science to research under much pressure. However, after a lifetime of wondering, it was not until early 2371 that Odo discovered he was one of 100 changeling Founders sent out at an unspecified earlier time as an exploratory contact mission from the Dominion, implanted genetically with the need to return home someday.

Initially it was only the formative Odo's duplication of his container, a Krokian Petri beaker, that alerted Mora to his sentience. Even after gaining intelligence, communication skills and a refined morphing ability he'd had trouble with "social integration," Mora noted. His name stems from the Cardassian words for "nothing" — the literal translation of "Odo'ital," which Dr. Mora's Cardassian overseer took as the meaning of his intended specimen label "Unknown Sample" that was affixed to his container. After he was known to be sentient, the native scientists as a joke "Bajorized" it into "Odo Ital," and later just "Odo." The irony of the name "Nothing" was not lost on the homeless, friendless alien then, who turned the self-image around after the coming of Kira and the Starfleet crew.

As he grew and matured his humiliation in this role only mounted, thanks to incidents such as those which culminated with his coerced performance in 2363 of a mocking "neck trick" for visiting Cardassian Central Command members, including Gul Dukat, and he walked out on Mora and the lab soon after. Even so, he kept his hair style, maintained after much practice, which was copied from Pol's, and the period reinforced his self-reliance.

After two years of building a reputation as a neutral arbiter settling simple squabbles among Bajorans, he was coerced by Dukat into solving a murder on DS9 (then Terok Nor), where he met Quark and mysterious resistance-fighter Kira for the first time. The case went unsolved for five years, but he eventually realized the murderer was indeed Kira, taking vengeance on a turncoat Bajoran collaborator.