sui generis

adjective

sui ge·​ner·​is ˌsü-ˌī-ˈje-nə-rəs  ˌsü-ē-ˈje- 

-ˈge-

: constituting a class alone : unique, peculiar

Did you know?

Many English words ultimately trace back to the Latin forms gener- or genus (which are variously translated as “birth,” “race,” “kind,” and “class”). Offspring of those roots include general, generate, generous, generic, and gender. But sui generis is truly a one-of-a-kind genus descendant that English speakers have used to describe singular things since the late 1600s. Its earliest uses were in scientific contexts, but where it once mostly characterized substances, principles, diseases, and even rocks thought to be the only representative of their class or group, its use expanded by the early 1900s, and it is now used more generally for anything that stands alone.

Synonyms

• only
• one
• lone
• special
• unique

Examples of sui generis in a Sentence

among history's greats Leonardo da Vinci is often considered sui generis—a man of such stupendous genius that the world may never see his like again

Recent Examples on the Web

Most of them consider Trump as a sui generis political figure who voters don’t associate with the GOP’s least popular ideas. —David Weigel, semafor.com, 4 July 2025

This is all the more surprising given that each diagram is highly particular, practically sui generis. —Jonathon Keats, Forbes.com, 30 June 2025

But disruption was the point of Lunch Dances, the latest project of Monica Bill Barnes & Company, a sui generis enterprise with a mission to bring dance to unexpected places and in conversation with unlikely partners. —Brian Schaefer july 7, Literary Hub, 7 July 2025

Almost all of Weill’s projects were sui generis, rejecting routine and experimenting anew. —Alex Ross, New Yorker, 14 Apr. 2025

Word History

Etymology

Latin, of its own kind

First Known Use

1615, in the meaning defined above

Rhymes for sui generis

• ungenerous
• generous

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Legal Definition

sui generis

adjective

sui ge·​ner·​is ˈsü-ˌī-ˈje-nə-rəs, ˈsü-ē- 

: constituting a class alone : unique or particular to itself

the lawyer's…ad that makes no distinction among various legal and factual nuances in each sui generis case has the potential to mislead

—National Law Journal

Etymology

Latin, of its own kind