Moodboard
A collected set of visual references that fixes the look, without specifying the shots.
A moodboard is reference: stills, frames, palettes, typography, grade examples. It communicates how the piece should feel and look rather than what happens in it.
It's the fastest way to close the gap between two people using the same adjective to mean different things. "Cinematic" is a word four people will picture four ways. Six frames pinned to a board resolves it in a minute.
Reference each image with what you're pointing at. "This one for the grade, not the composition" prevents the most common moodboard failure: a crew faithfully reproducing the thing you didn't mean.
Where this comes up
They answer different questions and get confused constantly. What each one is for, when neither is worth making, and the cheaper thing that usually is.
A brief's job is to make one decision impossible to get wrong. Here are the nine sections that matter, and the three that quietly ruin most briefs.