It can refer to:
* Way of behaving or acting: "He has a very polite manner."
* Way of doing something: "She has a unique manner of speaking."
* Style or fashion: "The house was decorated in a Victorian manner."
If you're looking for synonyms for "manner", here are some options depending on the context:
* Formal: demeanor, bearing, conduct, deportment
* Informal: way, style, approach, technique
* Specific: etiquette, protocol, method, approach
Let me know if you have a specific context in mind, and I can help you find the most suitable word.