无中生有 is a four-character idiom (chengyu) that literally means 'to create something from nothing'. It describes statements, stories, or accusations that are completely fabricated, with no basis in fact. You use it to call out lies or baseless rumors. For example, 他说的全是无中生有 (tā shuō de quán shì wú zhōng shēng yǒu) means 'everything he said is pure fabrication'. Unlike English 'fabricated', the Chinese idiom carries a strong negative judgment and is often used to accuse someone of lying.