by definition

Prepositional phrase

1. According to, or as a matter of, definition.
   • This property holds for all polygons; and since, by definition, all triangles are polygons, it holds for all triangles.

   Synonyms:

   basically, deep down, essentially

2. Necessarily; always; certainly.
   • Almost by definition, a conversation requires both parties to accept each other's viewpoints to some extent.
   • Two minutes later, the Aston Villa man delivered. It was hardly the sweetest strike, but nobody cared. It wasn't particularly pretty, not that it mattered. It only found its way into the Haiti net by way of a double deflection but that was completely irrelevant.
     It was a Scottish goal in their...2026 June 14, Tom English, “Why Haiti v Scotland was antidote to the ills of world football”, in BBC Sport

   Synonyms:

   inevitably, inexorably, unavoidably