n. A memorandum of something that is likely to be again referred to; a fact or quotation or argument that is or may be made useful in one or another way or in a variety of ways, and so is made note of for handy use.n. A well-known, customary, or obvious remark; a trite or uninteresting saying.n. Anything occurring frequently or habitually; anything of ordinary or usual character; especially, anything that is so common as to be uninteresting; such common things collectively.Not novel or striking; trite; hackneyed: as, a commonplace remark.Ordinary; common; uninteresting; without originality or marked individuality: as, a commonplace person.To enter particulars regarding in a commonplace-book.To indulge in commonplace statements.