- Star Trek: The Motion Picture
- Star Trek II: The Wrath of Khan
- Star Trek III: The Search for Spock
- Star Trek IV: The Voyage Home
- Star Trek V: The Final Frontier
- Star Trek VI: The Undiscovered Country
- Star Trek Generations
Component used in the Delphic Expanse to insulate ships — it protects them from the mysterious anomalies that plague this area of space. According to chemist B'Rat, it is rare and difficult to process.
B'Rat provided Captain Archer with the formula for synthesizing trellium-D — though he warned that it is very volatile in its liquid state.