* Noun: This is the most common usage, referring to a person who works, especially for wages.
* Example: "The worker was tired after a long day."
* Adjective: This usage describes something related to work or workers.
* Example: "The worker's union negotiated a new contract."
* Verb: This is less common, but it can be used to mean "to work."
* Example: "I worker hard to finish the project on time."
The specific part of speech depends on the context of the sentence.