To be prepared to help or take action if needed.
Examples
The emergency team will stand by in case anything goes wrong.
A: Are you coming with us now?
B: No, I'll stand by and wait for your call if you need help.
Common mistake
Not: We are standing by for help you.
Say: We're standing by to help you.
'Standing by TO + verb' — not 'for'.
More on “stand by”Another example · Tell it apart · Goes with · Tip
Another example
In my opinion, it's important for doctors to stand by during big public events in case of accidents.
Tell it apart
We're standing by to assist.
We're standing by our decision.
Goes with
- stand by + readiness