Noun:
* A sharp: This refers to a pointed object, like a knife or a pencil.
* "He used a sharp to open the package."
Adjective:
* Describing something with a pointed edge: "The knife has a sharp blade."
* Describing something with a strong or sudden change: "There was a sharp increase in prices."
* Describing something intelligent or clever: "She has a sharp mind."
To determine if "sharp" is a noun or an adjective, you need to look at how it's used in the sentence.