English Phrasal Verb – Plug In
plug in [phrasal verb] to connect a piece of electrical equipment to the main supply of electricity or to another piece of electrical equipment
“Is the printer plugged in?”
electrical outlet ↑
We can also plug something in/into something.
“Plug the flash drive into the USB port on the side of your computer.”
The opposite of plug in is unplug.
“Please unplug the hair dryer when you are done.”