Trill (or Trills) is the name of a humanoid species native to the planet Trill. A small percentage of the Trill population co-exists with a sentient symbiotic organism known as a symbiont inside their bodies. The resulting joined Trills have personalities which are a synthesis of the two beings including the memories, and to some extent the personalities, of the previous hosts of the symbiont. This way, the joined being gains all the skills and occupations of the previous hosts.
Most Trills are distinguished by two rows of spots going down each side of their bodies, from forehead to toe. Their skin color could vary. One of the main neurotransmitters in the Trill brain is isoboramine. One Trill peculiarity is that they are known for having cold hands.
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