Something that is plain is very simple in style. Bronwen's dress was plain but it hung well on her fancy, elaborate + plainly plain·ly He was very tall and plainly dressed
extensive tract of level open land; "they emerged from the woods onto a vast open plain"; "he longed for the fields of his youth"
comprehensible to the general public; "written for the popular press in plain nontechnical language"
emphasis You can use plain before an adjective in order to emphasize it. The food was just plain terrible. Plain is also used before a noun. Is it love of publicity or plain stupidity on her part?