ping
To send a quick message or signal to get attention.
When you ping someone, you send them a quick message to get their attention or check if they're available. A parent might ping you on your phone to see if you're ready to be picked up from soccer practice. Your friend might ping you to ask if you want to hang out later. The word suggests a brief, light contact, like tapping someone on the shoulder rather than having a long conversation.
The word comes from sonar technology, where submarines and ships send out sound waves that bounce off objects and return with a distinctive “ping” noise. This lets them detect what's around them underwater. When your computer pings another computer on the internet, it's doing something similar: sending a quick signal to check if the other computer is there and waiting for a response.
You might also hear someone say “put that on my radar” or “that's not even on my radar yet.” When something pings your radar, it catches your attention or reminds you of something important. A teacher's comment about an upcoming project might ping your memory that you need to start working on it soon.