For other uses, see Adamant.

The IRW Adamant was a Warbird in service to the Romulan Star Empire in the late 23rd century. As of 2296, the Adamant was under the command of Commander Avrak.

In that year, the Adamant crossed the Romulan Neutral Zone into the Loki system, landing covert troops on the planet Obsidian in order to undermine the Starfleet mission there. The warbird was discovered there by the USS Intrepid II, but rather than declaring a state of war, Captain Spock allowed them to withdraw its people and return to Romulan space.

Also among the crew of the Adamant were Centurion Ruanek, and his cousin, Kharik. (TOS novel: Vulcan's Forge)