No shit, Sherlock.

When someone says someone is a dumbass and you become a smartass.

Sherlock: "It's cold today."

Watson: "No shit, Sherlock."

Sherlock: "F*ck you, Watson."

Smad

When younger siblings make you sad but also mad at the same time.

(Over snap)
Person 1: She's making me sad and mad.
Person 2: HAHAHA SMAD! That's a new word now!
Person 1: HAHA yes!!!!