(noun) a day that starts out crappy but then spirals out of control, becoming crappier and crappier and crappier, as if the total decline of your life would never end.
A parking ticket, blown math quiz, and now my kid has scabies. I'm on a shit-day slalom.
a day so totally crappy that it seemed like a race down a winding, spiraling, horrendous F-you course, marked by more and more notable shittiness happening to you at blinding speed, one event after another, and accruing more crappiness at every moment, totally beyond your control, until the end.
Man. Joe was caught waxing it in the office bathroom, then heard that his girlfriend cheated on him, THEN got a $325 speeding ticket on the way home. He's had a total shit-day slalom.