Untruth.
irony
This word does not have an opposite.
The opposite of the word "answer" is "question."
The adverb form of the word truth is truthfully.
Truth is a noun.
the opposite word of resentment is loyal truth;kindness,happyness
Mendacious
reality, truth
The opposite word of rumor monger is truth-teller or fact-checker.
"mensonge" means "lie", the opposite of truth.
I think Stephan Colbert declared 'Truethiness' to be a word, but its means something quite opposite of 'truth'.
The antonym (opposite) of the word fantasy would be reality, or truth.
Truth
The opposite word for myth is truth. 'Fact' is also an acceptable synonym.
truth
the truth
"Tale", or story, has no opposite.