A blue side is a feeling of emptiness and sadness. An act of hopelessness. It can also be an example of depression.
Jerry: Bob, are you on the blue side again?
Bob: Just a little. ...
82π 4π
The feeling of longing for someone whom you canβt seem to have
Ren: Omg I think I love him but like...
Holly: blue side?
Ren: yep, blue side
22π 13π
Salutation; refers to the artificial horizon indicator on an aircraft instrument panel. Blue represents sky and black represents the ground. If the black side is up, this will not end well. Similar to truckers' salutation of "Keep it between the paint" and satirical theatrical salutation of "Break a leg."
Said to a spouce: "See ya later, honey; keep the blue side up!"
To a friend: "Remember to keep the blue side up!"
54π 6π