Seemingly factual quality, informally

• Stephen Colbert-coined word meaning the quality of an assertion that makes it "just feel right"
• Political deception (Stephen Colbert)
• Modern coinage meaning intuition without regard to facts
• Subject of "The Word" on the first episode of "The Colbert Report"

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
"act or quality of preferring concepts or facts one wishes to be true, rather than those known to be true," a catch word popularized in this sense by U.S. comedian Stephen Colbert (b.1964), declared by American Dialect Society to be "2005 Word of the Year." ...

Wikipedia Word definitions in Wikipedia
Truthiness is a quality characterizing a " truth " that a person making an argument or assertion claims to know intuitively "from the gut" or because it "feels right" without regard to evidence , logic , intellectual examination, or facts . American television ...

Wiktionary Word definitions in Wiktionary
n. (context rare archaic English) truthfulness. (from 19th c.)