tertium quid

American  

[tur-shee-uhm kwid, ter-ti-oom kwid] / ˈtɜr ʃi əm ˈkwɪd, ˈtɛr tɪˌʊm ˈkwɪd /

noun

1. something related in some way to two things, but distinct from both; something intermediate between two things.

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tertium quid British  

/ ˈtɜːtɪəm ˈkwɪd /

noun

1. an unknown or indefinite thing related in some way to two known or definite things, but distinct from both

   there is either right or wrong, with no tertium quid

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Etymology

Origin of tertium quid

1715–25; < Latin, translation of Greek tríton·ti some third thing

Example Sentences

In this case, this blog is a tertium quid to my other two blogs—it’s related to them but something different altogether.

From Forbes

New departures in both tragedy and comedy, and a theatrically important tertium quid were all instituted.

From Project Gutenberg

That the mind can conceive of something between the infinite and the absolute, which is neither the one nor the other, but a tertium quid—the conditioned.

From Project Gutenberg

It is clearly not a strychnia effect pure and simple, nor an iron effect only; it is a tertium quid compounded of the actions of both drugs.

From Project Gutenberg

Therefore, without any definite conceptions as to its inherent alliances, we speak of it as possibly something between the other two—a tertium quid.

From Project Gutenberg