Convention
Etymology
From Latin "conventio" (an agreement, a coming together), from "convenire" (to come together), from "con-" (together) and "venire" (to come). A convention is, at root, something people have come together on — its authority rests on collective assent, not on force or fact.
noun · /kun-VEN-shun/
An accepted practice or rule that holds by shared agreement rather than by law or nature.
What it names
The vast body of "how things are done" that binds us without being written down — and that could, in principle, have been otherwise.
Example
That we drive on a particular side of the road is pure convention — arbitrary, but disastrous to break unilaterally.
Related idea
A convention holds because we tacitly agree to it and could coordinate on another; a law holds by formal enforcement — breaking a convention is awkward, breaking a law is punishable.
noun · /kun-VEN-shun/
A large formal gathering of people with a shared interest or purpose — political, professional, or fan.
What it names
an organized mass meeting
Example
Delegates from every state gathered at the party’s national convention.
Related idea
A fan convention is where a fandom stops being scattered and online and becomes, for a weekend, a crowd in a room.
noun · /kun-VEN-shun/
A formal agreement or treaty between states or parties, especially on a specific matter.
What it names
an international or formal accord
Example
The Geneva Convention sets binding rules for the treatment of prisoners of war.
Related idea
Such a convention exists largely to constrain what any belligerent may lawfully do.