The term "shocker" can have different meanings depending on the context. Here are some possible definitions:

• Utmost surprise: According to Urban Dictionary, "what a shocker" is a phrase used to denote utmost surprise at a certain event or happening. It can also be used sarcastically.
• Something horrifying or offensive: Merriam-Webster defines "shocker" as something that shocks, especially something horrifying or offensive, such as a sensational film or work of fiction.
• Something that shocks people: Collins Dictionary defines "shocker" as something such as a story, a piece of news, or a movie that shocks people or that is intended to shock them.
• Something likely to offend: Cambridge Dictionary defines "shocker" as something that is likely to offend, especially something new or recently announced.
• One who or that which shocks or startles: Wiktionary defines "shocker" as one who or that which shocks or startles, such as a sensational novel, play, or movie.
• A person or thing that shocks: Dictionary.com defines "shocker" as a person or thing that shocks, such as a sensational novel or play.

In summary, "shocker" can refer to something that causes surprise, horror, offense, or shock, or to a person or thing that has a shocking effect.