To "Agnew" is to laugh at a private joke, which you are not part of.
Different uses:
To agnew, to have agnewed, to be an agnew, epic agnew
Sam: Remember that time me and you were in Mikes car and rolled up on that dude and that underaged girl making love?"
Oli: hahaha, we weren't afraid to hit people in the face
Rob: hahahaha
Sam: Rob, you just pulled a total agnew
Spiro Agnew was VP under Nixon until resigning in the wake of a criminal indictment. After Nixon resigned due to Watergate, Agnew naturally became a follow on joke when someone used the word "Nixon" when referring to taking a shit or a bowel movement.
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.