Complex ideas often get boiled down into slang or jargon - shortcuts to describe something hard to articulate. When people connect with that shortcut, they reuse it. The process repeats.

Like in baseball - if there’s a runner on 1st, 2nd, and 3rd, we just say the “bases are loaded.”

“Bases loaded” quickly conveys the full situation. That phrase caught on.

Like what?

Like wildfire.

How did it spread?

Like wildfire. Wildfires spread fast, in every direction, and nothing really stops them. You could say it went viral.

Viral?

Yeah - viral.

Viral how?

Well… like a virus.

See?