Twi’leks were a species of tall humanoids whose skin spanned a vast array of colors, including white, orange, yellow, green, pink, blue, purple, black, grey, and red. Their most distinctive feature was the pair of prehensile appendages that sprouted from the crown or base of their skulls, known as lekku, or head-tails. Although Twi’leks normally had two lekku, some individuals had four. Super sensitive lekku could grab and hold objects and react to the slightest touch. A damaged lekku could cause serious harm to a Twi’lek’s health.

The species had two sexes, male and female. While most males typically had ears with lobes resembling those of humans, some males had cone-shaped hearing organs located in the same place on the head, a trait customarily found in the females of the same species. Although Twi’leks naturally had blunt teeth, males typically sharpened them to points.

Twi’leks were usually thin, although corpulent individuals were known to exist. Under normal circumstances, they generally had a higher body temperature than other humanoid species. They had even higher body temperatures when in fear.

Twi’leks and humans could breed to create a hybrid of the two species: shortly after the death of Kanan Jarrus, he and Hera Syndulla gave birth to a son who appeared mostly human but inherited his mother’s green pigment in his hair and ears. He was born after the liberation of Lothal, in which Syndulla lived to participate.

The Twi’leks had a language of their own, called Twi’leki, which combined verbal sounds and an elaborate, subtle sign language using their lekku. Twi’lek’s lekku could be moved to create gestures with meanings such as hello or goodbye. For example, both lekku tips crossed twice meant, “I love you.” Twi’leks were capable of speaking Galactic Basic Standard, many with a noticeable accent; although it was possible for some to lose this accent if away from Ryloth for an extended period of time, it could still resurface. For example, Hera Syndulla lapsed back into the common Twi’leki accent during an argument with her father and also used it consciously when passing herself off as a slave.

Mynock Cloud City and Mynock Coronet City were spicy dishes made from mynocks that were popular with Twi’leks, as well as a dish known as fried mynock. Twi’leks were eaten by gutkurrs, vicious insect carnivores that used their sharp, curved claws to snare their prey.