Catchphrase

A catchphrase is a phrase caught up and repeated in common everyday speech. According to the OED, it first appeared in print c. 1922. It is derived from the older word, catchword, dating from the 18th century, which refers to a single word caught up and repeated, especially in party politics. In printing, a catchword is the first word of the following page inserted at the right-hand lower corner of each page of a book, below the last line. Sometimes, it was also the opening word of a new chapter, printed in bolder type to catch the eye. Neither of these practices is commonly used in printing books these days.