vi to utter commonplaces; to indulge in platitudes.
2. commonplace ·vt to enter in a commonplace book, or to reduce to general heads.
3. commonplace ·adj common; ordinary; trite; as, a commonplace person, or observation.
4. commonplace ·noun a memorandum; something to be frequently consulted or referred to.
5. commonplace ·noun an idea or expression wanting originality or interest; a trite or customary remark; a platitude.