The small one-man craft used by Lazarus to travel between the universe of matter and its antimatter twin, destroyed by the Enterprise in 2267 to seal the passage between them.
Lazarus's ship is a small domed craft found on a barren planet in the episode The Alternative Factor. Lazarus describes it at first as a time ship. It is really the doorway to a corridor linking two universes, one of matter and one of antimatter.
There are two men named Lazarus and two versions of the ship, one in each universe. The mad Lazarus steals dilithium crystals from the Enterprise to power his, meaning to reach and kill his sane counterpart, although their meeting outside the corridor would annihilate both universes.
Kirk forces the mad Lazarus through the doorway, where his double holds him. The Enterprise then destroys the ship with its phasers, leaving both men locked in the corridor for all time.