English Reference
Idiom idiom

de facto

C1 Formal Roman origin
Meaning

In practice, whatever the official position says.

Examples
SIMPLE

“She has no title, but she is the de facto manager.”

CONTEXTUAL

“English has become the de facto language of the conference, whatever the programme says.”

COMPLEX

“The format was never ratified by any standards body and became the de facto standard anyway, which is how most standards are actually made and almost none are officially described.”

Origin

Roman law drew a hard line between a question of fact and a question of law, and a great deal of Roman legal reasoning consists of sorting one from the other. De facto — from the fact — is the label for the first side of that line.

The paired tags de facto and de jure were sharpened by medieval and early-modern jurists, who needed a clean way to describe rulers who held power without a legal title. A de facto government is the one actually governing; a de jure government is the one entitled to. For long stretches of European history these were different people, sometimes in different countries.

English uses de facto far beyond the law, for any arrangement that is real without being official — a de facto capital, a de facto standard, a de facto deputy who has never been given the job.

The Law's Latinconnected storiesSee all Roman origin →

Roman legal Latin that never left the courtroom — or the boardroom.

  1. 01

    bona fide (idiom)

    Genuine and honestly meant — the real thing, not a pretence.

    The Roman standard of good faith.
  2. 02

    caveat emptor (idiom)

    Let the buyer beware — checking what you are buying is your own problem.

    What Rome did not actually say.
  3. 03

    quid pro quo (idiom)

    Something given in return for something else, usually as an understood trade.

    From the apothecary's substitute.
  4. 04

    de jure (idiom)

    According to the law, whether or not that is what actually happens.

    The question of law.
  5. 05

    ipso facto (idiom)

    By that very fact — the consequence follows automatically, with no further step.

    Consequences that need no hearing.
  6. 06

    the status quo (idiom)

    The way things currently are, especially when someone wants to keep them that way.

    In statu quo ante bellum.

Last updated August 3, 2026