catchword

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A well-known word or phrase, especially one that exemplifies a notion, class, or quality: "We're turned off by the label 'sexy' when used as a catchword for every new design” ( Miriam Lang).
2. n. A catchy name or slogan: "the top management of major corporations . . . busy coining catchwords for their new management concepts” ( Japan Economic Journal).
3. n. Printing A guideword.
4. n. Printing The first word of a page printed in the bottom right-hand corner of the preceding page.

Century Dictionary and Cyclopedia

1. n. In old writing and printing, a word of the text standing by itself in the right-hand corner of the bottom of a page, the same as the first word of the next page, to mark the connection or proper sequence. In old manuscript books a catchword was at first inserted only at the end of a sheet or quire (that is, the quantity folded together); in printing it was the practice until the nineteenth century to insert one at the foot of every page.
2. n. In the drama, the last word of a speaker, which serves to remind the one who is to follow him of what he is to say; a cue.
3. n. A word caught up and repeated for effect; a taking word or phrase used as a partizan cry or shibboleth: as, the catchword of a political party.

Wiktionary

1. n. A word under the right-hand side of the last line on a book page that repeats the first word on the following page.
2. n. A word or expression repeated until it becomes representative of a party, school, business, or point of view.

GNU Webster's 1913

1. n. Among theatrical performers, the last word of the preceding speaker, which reminds one that he is to speak next; cue.
2. n. (Print.) The first word of any page of a book after the first, inserted at the right hand bottom corner of the preceding page for the assistance of the reader. It is seldom used in modern printing.
3. n. A word or phrase caught up and repeated for effect

WordNet 3.0

1. n. a favorite saying of a sect or political group
2. n. a word printed at the top of the page of a dictionary or other reference book to indicate the first or last item on that page