anom·a·ly 
/əˈnɑ:məli/ noun
plural anom·a·lies /əˈnɑ:məli/ noun [count] somewhat formal : something that is unusual or unexpected : something anomalous
▪ A storm like that is an anomaly for this area. [=a storm like that does not usually happen in this area] ▪ We couldn't explain the anomalies in the test results. ▪ The doctor detected an anomaly [=irregularity] in my heartbeat.
▪ A storm like that is an anomaly for this area. [=a storm like that does not usually happen in this area] ▪ We couldn't explain the anomalies in the test results. ▪ The doctor detected an anomaly [=irregularity] in my heartbeat.
