Filed from 2 published puzzles

THATSO

Set to 2 different clues across 2 published puzzles, most often "Really?" — The New York Times, Sunday, 25 July 2010.

6 letters

Every clue on record, most used first

"Really?"once
The New York Times — Sunday, 25 July 2010
"You don't say"once
The New York Times — Sunday, 5 September 2004

Other answers to these clues

ANDHOW6 letters
AREYOUKIDDINGME15 letters
AREYOUSURE10 letters
DOTELL6 letters
EVERSO6 letters
GEE3 letters
GOSH4 letters
HONEST6 letters
IKIDYOUNOT10 letters
INDEED6 letters
ISITTRUE8 letters
ISTHATSO8 letters