› ACCOUNTING documents and records that show the history of a company's financial activities, examined by someone who is doing an audit (= checking a company's accounts): The audit trail must be supported by sufficient documentation to follow a transaction from beginning to end. You should maintain an adequate audit trail of all transactions.
› IT a record of the activity on a computer or computer system: It's important to keep an audit trail to see who has changed a document and when. The database provides a full audit trail of activity.