Merism (, ) is a rhetorical device (or figure of speech) in which a combination of two contrasting parts of the whole refer to the whole.

For example, in order to say that someone "searched everywhere", one could use the merism "searched high and low". Another example is the sword-and-sandal movie genre, a loose term for a genre of movies made principally in Italy in the 1950s and 1960s set in classical antiquity.