IPA: /æbˈnɔːr.məl/
KK: /æbˈnɔrml/
Not typical or usual; something that is different from what is considered normal, often in a way that may be concerning.
The doctor noted that the test results were abnormal and required further investigation.
A person who behaves or thinks in a way that is different from what is usual or expected.
The study focused on the behavior of abnormal individuals in social settings.
Abnormal is formed from "ab-" (meaning away from) and "normalis" (from Latin, meaning conforming to a standard). The word describes something that deviates away from what is considered normal or standard.
Think of something that is 'away from' ('ab-') what is 'standard' ('normalis') — that's why abnormal means not normal.