A species who communicate through narrative metaphors.
The Tamarians are a humanoid species whose language is built entirely on metaphor and references to shared stories. Their speech draws on legends, heroes and past events, so that a phrase naming a figure or a place stands in for a whole idea, and the Universal Translator can render the words but not their meaning.
Because of this, the Federation long found it difficult to hold any proper conversation with them. Tamarian culture treats stories as the basis of understanding, and an outsider who does not know the tales cannot follow what is being said. Their ships are of a design that has been seen near the El-Adrel system.
They appear in the Next Generation episode Darmok, in which Captain Dathon of the Tamarians takes Picard to a planet and leaves him to fight a beast together, in an attempt to bridge the gap between their peoples. Picard gradually understands Dathon's meaning. Dathon dies of his wounds, but his sacrifice teaches Picard how to communicate, and he is able to prevent a conflict with the Tamarians afterwards.