Delimiters is the term that I use for definite and indefinite articles. "Article" is a rather unclear and ambiguous term, as it can mean a piece of writing (e.g., a newspaper article), or an object or item (an article of clothing). The term delimiter is less confusing. I have chosen it because these forms delimit the intended meaning of a noun. For example, "coffee" is a material, but "a coffee" designates a coffee object (e.g., a cup of coffee), and "the coffee" designates coffee that is known to the listener.