COMMONPLACE, noun A memorandum; a common topic. COMMONPLACE, verb transitive To enter in a commonplace-book, or to reduce to general heads. COMMONPLACE-book, a book in which are registered such facts, opinions or observations as are deemed worthy of notice or remembrance, so disposed that any one may be easily found. Hence common-place as used as an epithet to denote what is common or often repeated, or trite; as a commonplace observation.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI