uni- — one, single (affix)

universe B1

/ˈjuːnəˌvɝs/ Everything that exists, including all of space, time, and matter.

uniform A2

/ˈjunɪˌfɔɹm/ A set of special clothes worn by members of a group, such as students, police, or soldiers.

unite B1

/juˈnaɪt/ To join people together for a common purpose.

unicorn C2

/ˈju.nɪ.kɔɹn/ A mythical horse, widely believed to exist until the 17th century, with a single, straight, spiraled horn projecting from its forehead.

unilateral C1

/ˌjuːnɪˈlætərəl/ affecting, occurring on, or involving only one side of the body or another structure

unicycle C2+

/ˈjunɪˌsaɪkəl/ a single-wheeled pedal-driven vehicle