n. 口号, 标语, 口头禅

Catchword \Catch"word`\, n.
1. Among theatrical performers, the last word of the
preceding speaker, which reminds one that he is to speak
next; cue.

2. (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. A word or phrase caught up and repeated for effect; as,
the catchword of a political party, etc.