Remain on top like a duvet should? (4,4)

I believe the answer is:

hold down

I'm a little stuck... Click here to teach me more about this clue!

'remain' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how they can define each other.

I can't explain the rest of the clue.

Can you help me to learn more?

(Another definition for hold down that I've seen is " Restrain".)

I've seen this clue in The Globe and Mail.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.