A credit event is the financial term used to describe either:

• A general default event related to a legal entity's previously agreed financial obligation. In this case, a legal entity fails to meet its obligation on any significant financial transaction (coupon on a bond it issued or interest rate payment on a swap for example). The marketplace will recognize this as an event related to the legal entity's credit worthiness.
• A financial event related to a legal entity which triggers specific protection provided by a credit derivative
  Credit derivative
  In finance, a credit derivative is a securitized derivative whose value is derived from the credit risk on an underlying bond, loan or any other financial asset. In this way, the credit risk is on an entity other than the counterparties to the transaction itself...
  
   (credit default swap
  Credit default swap
  A credit default swap is similar to a traditional insurance policy, in as much as it obliges the seller of the CDS to compensate the buyer in the event of loan default...
  
  , credit default swap index
  Credit Default Swap Index
  A credit default swap index is a credit derivative used to hedge credit risk or to take a position on a basket of credit entities. Unlike a credit default swap, which is an over the counter credit derivative, a credit default swap index is a completely standardised credit security and may...
  
  , credit default swap index tranche, etc.)

The events triggering a credit derivative are defined in a bilateral swap confirmation which is a transactional document that typically refers to an ISDA

International Swaps and Derivatives Association

The International Swaps and Derivatives Association is a trade organization of participants in the market for over-the-counter derivatives....

 master agreement previously executed between the two swap counterparties. There are several standard credit events which are typically referred to in credit derivative transactions:

• Bankruptcy
  Bankruptcy
  Bankruptcy is a legal status of an insolvent person or an organisation, that is, one that cannot repay the debts owed to creditors. In most jurisdictions bankruptcy is imposed by a court order, often initiated by the debtor....
  
  
• Failure to Pay
• Restructuring
  Debt restructuring
  Debt restructuring is a process that allows a private or public company – or a sovereign entity – facing cash flow problems and financial distress, to reduce and renegotiate its delinquent debts in order to improve or restore liquidity and rehabilitate so that it can continue its...
  
  
• Repudiation
• Moratorium
• Obligation Acceleration
• Obligation Default