Meaning 1 · most common
reduce speed

To move or do something more slowly, especially to avoid danger or because you are told to.
Examples
You should slow down when driving through a school zone.
A: You're driving a bit fast.
B: Oh, sorry! I'll slow down.
Common mistake
Not: You should slow down your speed.
Say: You should slow down.
'Slow down' already means reduce speed — 'slow down your speed' is redundant.
More on “reduce speed”Another example · Tell it apart · Goes with · Tip
Another example
If I notice someone tailgating me on the highway, I usually slow down to let them pass safely.
Tell it apart
Slow down, you're driving too fast.
Slow down, you're working too hard.
Goes with
- slow down + context
