From mis- + truth.
mistruth (countable and uncountable, plural mistruths)
- Untruth; falsehood.
- 1994, Nelson Mandela, Long Walk to Freedom, Abacus 2010, p. 81:
- In my brief stay in Johannesburg, I had left a trail of mistruths and, in each case, the falsehood had come back to haunt me.