sine qua non

noun

si·​ne qua non ˌsi-ni-ˌkwä-ˈnän  -ˈnōn 

also ˌsē-;

also ˌsī-ni-ˌkwā-ˈnän

plural sine qua nons also sine quibus non -ˌkwi-(ˌ)bu̇s- 

also -ˌkwī-

: something absolutely indispensable or essential

reliability is a sine qua non for success

Did you know?

Sine qua non can be translated literally as "Without which, not." Though this may sound like gibberish, it means more or less "Without (something), (something else) won't be possible." Sine qua non sounds slightly literary, and it shouldn't be used just anywhere. But it actually shows up in many contexts, including business ("A solid customer base is the sine qua non to success"), show business ("A good agent is a sine qua non for an actor's career"), and politics ("His support was really the sine qua non for her candidacy").

Synonyms of sine qua non

• must
• requirement
• necessity

Examples of sine qua non in a Sentence

Patience is a sine qua non for this job.

an extensive grounding in mathematics is a sine qua non for a career in architecture

Recent Examples on the Web

If cultural similarity were the sine qua non of syncing up, then homogenous rosters would be the recipe for success. — Michael Morris, Time, 1 July 2026

Many other analysts on Wall Street see the reusability of Starship as the sine qua non of the company’s long-term profitability. — Tobias Burns, CNBC, 1 July 2026

According to Taylor, the Model Context Protocol (MCP) is a sine qua non. — David Doty, Forbes.com, 19 June 2026

Demanding better services at lower costs is the sine qua non for growing prosperity. — Wayne Winegarden, Oc Register, 3 May 2026

Word History

Etymology

Late Latin, without which not

First Known Use

1602, in the meaning defined above

Rhymes for sine qua non

• agamemnon
• automaton
• diencephalon
• panopticon
• phenomenon
• aileron
• antiphon
• autobahn
• carillon
• castellan
• celadon
• cephalon