A bounced cheque (also called a dishonored cheque or NSF cheque) is a check that the bank refuses to process because the account does not have enough money to cover it. The check literally "bounces" back unpaid.
When a cheque bounces, both parties face consequences. The bank charges the issuer a penalty fee (typically $25-40 in the US) and may charge the depositor a returned-item fee too. The issuer's credit score and banking reputation take a hit.
In many countries, issuing a bounced cheque is a criminal offense. In India, under Section 138 of the Negotiable Instruments Act, it can lead to imprisonment up to 2 years and/or a fine. In the UAE, bounced cheques were historically treated as serious crimes, though recent reforms have softened penalties.