Deviation

noun a departure from what is normal, usual, or expected, typically one that is unwelcome

• The scientist considered the unexpected result to be an aberration in his data.
• That weird data point was a total aberration, dude.
• The glitch in the system was a total aberration, like, what even happened?
• Her behavior at the party was an aberration from her usual reserved demeanor.

noun a deviation from what is normal or typical

• The doctor detected an abnormality in the patient's blood test results.
• There was something abnormal in the test results the doctor found.
• The test results were totally whack with some abnormality showing up.
• The abnormality in the data was like a red flag waving in front of us.