A cardinal rule in designing an API is being consistent. You will face many choices when it comes to defining your endpoints and methods, and some may be better than others. However, when it comes to providing consistent conventions, for naming and overall method mechanics, you must not bend. Giving a resource or parameter one name here, and addressing it with a completely different name some place else is a cardinal sin not easily forgiven.
Moving further up the data chain, Brian Fenton (Mashery Sr. Software Engineer), on his personal blog, wrote about the value of database naming conventions, covering tables, linking tables and columns. Brian’s insight and experience on this topic should be helpful at both the database and API design stages. Read his blog post here. Also, he recently gave a talk at Sunshine PHP on this topic, and you can view his slide deck below: