What in Tarnation is Grammar Girl talking about this week?

Grammar Girl here. I'm in Yon Fogarty and you can think of me as your friendly guide to the English language.

We talk about writing, history, rules, and other cool stuff.

This week we'll look at the difference between slow down and slow up,

and we'll have fun exploring some minced oaths.

I love listener questions and we got an interesting one recently.

Hi, Grammar Girl. I wanted to ask a question about the expression slow down.

So many years ago I was watching an episode of the show, Comps.

And I remember a police officer describing his apprehension of her suspects.

And he said that he slowed up.

So I'm from the Pacific Northwest and from the officer's accent.

I was sure he was from the East Coast.

I understood him as meaning that he slowed down to speak to a person of interest.

I've been wondering over the years about the expressions slow up versus slow down.

Slow up seems to mean you decreased your speed.

Slow down seems to indicate that you're going faster.

Slow up feels to make more sense to me than saying slow down.

If I want to mean that someone is going slower.

My question is, is using slowing up to mean slowing down, grammatically incorrect?

And if so, why?

Thank you so much for all your wonderful work.

This is a great question.

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