The phrase 'centering on' means 'focusing on' or 'concentrating on'. It is often used to describe a topic or theme that is being explored or discussed. There are several synonyms for 'centering on', including 'revolving around', 'referring to', 'concerning', 'dealing with', and 'pertaining to'. These words can be used interchangeably with 'centering on' to convey the same meaning. Using synonyms can add variety to your writing and help you avoid repetitive language. They can also be used to emphasize a particular aspect of a topic or theme, depending on the context in which they are used.