Mythos
Etymology
Greek "mythos" first meant simply speech or story, and Aristotle’s Poetics used it for the plot of a drama. Over centuries it split from "logos," coming to name narrative and myth as against logical account. English "myth" and "mythology" descend from it.
noun · /MY-thoss/
The traditional story or narrative framework a culture lives by, as opposed to reasoned argument.
What it names
The story-shaped truths a people holds — the founding tales that organize meaning below the level of argument.
Example
No amount of fact-checking dented the movement, because it ran on mythos — a shared story about betrayal — rather than on evidence.
Related idea
The narrative counterpart to logos; a culture’s mythos hardens into the kind of grand story a metanarrative tries to name.