expression, noun
Refers to a standard that is widely accepted and used in practice, even if not formally established. Often used in technology and business contexts.
See also: デファクトスタンダード
このファイル形式は事実上の標準になっている。
This file format has become the de facto standard.
Synonymous loanword from English. 事実上の標準 is the native Japanese equivalent, often used in more formal or explanatory contexts.
Compound of 事実上 (de facto, in practice) + の (possessive particle) + 標準 (standard).