plain

Universal Words adjective, noun, adverb adjective (plainer, plainest) 1 easy to see or understand: He made it plain that we should leave. * She made her annoyance plain. * The facts were plain to see. 2 not trying to trick anyone; honest and direct: The plain fact is that nobody really knows. * a politician with a reputation for plain speaking * (especially AmE) a plain, straightforward sort of man 3 not decorated or complicated; simple: a plain but elegant dress * plain food / cooking * The interior of the church was plain and simple. * plain yogurt (= without sugar or fruit) compareFANCY 4 without marks or a pattern on it: covers in plain or printed cotton * Write on plain paper (= without lines). 5 [onlybeforenoun] used to emphasize that sth is very ordinary, not special in any way: You don't need any special skills for this job, just plain common sense. 6 (especially of a woman) not beautiful or attractive plainness noun [U] IDIOMS be plain sailing (AmE also clear sailing) to be simple and free from trouble in plain English simply and clearly expressed, without using technical language: a document written in plain English * If you could put it in plain English I might be able to understand. (as) plain as a pikestaff