(Can we verify(+) this sense?) To leave a place, or a meeting, without being noticed
1982,John Le Carré,The Quest for Karla, page 162:
Soon as he could, he slid off to Jim's rooms to make sure he'd left nothing around that a journalist might pick on if a journalist were clever enough to make the connection, Ellis to Prideaux.
2009,David Nobbs,I Didn't Get Where I Am Today, ISBN 1409066967, page 444:
Susan and I slid off to an Indian restaurant in Shepherd's Bush, and I slid off on to the floor.
2011,Lamont Z. Brown Phoenix King, & Lamont Z. Brown,Between the Gates of Heaven and ****, ISBN 1426952619, page 10:
As Simone and the crowd praised Drew I slid off to the back hurt, ashamed, and pissed off.