Undertable money refers to the illegal act of giving or receiving bribes or secret payments. Synonyms for this term include black money, dirty money, hush money, bribe money, illicit money, under-the-counter money, payola, and kickback. These synonyms are used to describe money or payments that are made in secret and are usually unethical or illegal. The act of giving or receiving undertable money is considered corrupt and undermines the fairness and transparency of any transaction or business deal. It is important to report any instances of undertable money to the appropriate authorities to prevent further corruption.