I know the historical ones didn't look like this, but whenever anyone says "flint and steel" in a non-Minecraft context I imagine a Bunsen burner striker.

(Which actually is a kind of flint and steel! Though the "flint" is probably ferrocerium.)

banana to banana communication (ethylene)

the weak horse, the strong horse, the electromagnetic horse, and the gravitational horse

I understand the practical reasons behind it but every time I encounter the term “kilowatt-hour” I’m all “okay but what is that in joules”.

(The answer is 3.6 MJ.)