Any condition that deviates from expectation based on requirements specifications, design documents, user documents, standards, ete. orfrom someone's perception or experience. Anomalies may be found during, but not limited to, reviewing, testing, analysis, compilation, or use of software produets or applicable documentation. [IEEE 1044] See also bug/defect, deviation, error, fault, failure, incident, problem.
Terms of Software Testing (ISTQB)