liar's loan Share definition Flag A "no-doc" or "low-doc" mortgage that does not require documentation of income. Even with his income, couldn't qualify for a large enough loan for the McMansion he wanted, so he got a "liar's loan." liar's loan by Voltron2 September 30, 2006 0 0 Get merch Get the liar's loan mug. Buy Now — $32.95 See more merch