* Adjective: This is the most common use, describing something that deviates from the normal or expected.
* Example: "The doctor noted an abnormal heart rhythm."
* Noun: It can also be a noun, referring to something that is abnormal.
* Example: "The scientists studied the abormalities in the data."
* Adverb: Less common, but it can be used as an adverb, meaning "in an abnormal manner."
* Example: "The plant grew abnormally large."
The specific part of speech depends on the context of the sentence.