What are the Trill in Star Trek? Explained

In many ways, it’s easy to explain the Trill of Star Trek. They are a humanoid species from the planet Trill located in the Alpha Quadrant. They look just like Humans except for the cluster of dark spots running along the sides of their heads and – though it’s often unseen for censorship purposes – along their bodies. There’s an aspect of Trill culture that’s a little more difficult to explain, though, but I’ll give it a try anyway.

What is a Trill?

The Trill are as scientifically advanced as most alien races throughout the galaxy of Star Trek. They, too, love to put things under a microscope and study them in official research capacities. It’s potentially in their pursuit of knowledge that they discovered a long, long time ago that some of them had the ability to link with a Trill symbiont.

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They undergo surgery during which a big worm is placed in their abdomen. This process forms an immediate connection between the host and the symbiont. The two then embark on a lifelong journey of sharing memories and life experiences after they are joined. It’s not such an easy concept to explain to anyone new to fandom.

The Trill were first introduced in Star Trek: Deep Space Nine and have been a have since become staple of the franchise. We even got to see the ancient underground pools where Trill went to better understand, or sometimes heal, the symbiont within them.

Notable Trill in Star Trek

However, Deep Space Nine didn’t just introduce the Trill or their cultural practices. The series gave us the most famous Trill of all: Jadzia Dax. She was the First Officer and BFF of Captain Sisko. She was also the closest that many transgender Star Trek fans had ever gotten to complex representation in a popular sci-fi series.

As much as we love (and miss) her, though, Jadzia was not the only Trill to get into space shenanigans like time travel and facing one’s own insecurities. She came from a long line of Trill who’d joined with the Dax symbiont. Some of whom we met in Deep Space Nine, like the incorrigible Curzon or the emphasis Ezri.

Then, of course, there’s Barnes in Lower Decks and Gray Tal in Discovery. Technically, there’s also Adira Tal but that complicated history is for another time. Just know that explaining the Trill of Star Trek just got a little easier. You’re welcome!