Phrasal Verb > Plug in
1 : plug (something) in or plug in (something) : to connect (something, such as a lamp or television) to an electrical source or to another device by using a plug
Don’t plug the stereo in yet.
He plugged in the lamp.
The microphone isn’t plugged in.
2 : to put (information, such as a word or number) in something
The form has spaces where you just plug in (=insert) your name and address.