* Noun: This is the most common use. It refers to something that makes a situation more difficult or complex.
* Example: "The surgery was successful, but there were some complications afterwards."
* Verb: It can be used as a verb meaning to make something more complex or difficult.
* Example: "Don't complicate things by adding more ingredients."
* Adjective: While less common, it can be used as an adjective meaning "complex" or "difficult."
* Example: "The plot of the movie was very complicated."
It's important to look at the context of the sentence to determine which part of speech is being used.