This criss-cross study, the first of its kind, arranges a shotgun wedding between cliches and coinages - the old (that refuses to die), and new (that often quickly fades). Not such strange bedfellows, they jointly help to illuminate the running battle between the parasitic and the creative in our thought and language. Like puns, and against all defence-systems, they get everywhere. Cliches proliferate into proverbs, idioms, slogans, jargon, truisms, propaganda, racial stereotypes, rumour, education, kitsch. For their part, coinages permeate advertising, journalism, scientific terminology, poetry, schizophrenic language, acronyms, 'franglais'. Both purposeful and accidental neologisms (slips) are considered, with especial focus on blends. Coining is ambiguous: it embraces the mint-fresh and the forged. Just as neologisms feed mainly off fragments of existing words, so cliches can be recycled by being twisted to new purposes. The automatisms that beset us all can be subverted, or at least combatted. There are no automatic villians or heroes of this piece. A close analysis of plagiarism finds everyone guilty. Cliches are seen as essential social lubrication or balm, and coinages as a necessary counterweight to purism and linguistic refrigeration. Throughout, practice and theory in both areas are compared and contrasted, in the English, French and American traditions. Examples are taken from high culture, low life, and the level best where, of course, we all live. This text will be of interest to general readers and specialists in language studies in departments of French and English.