FIGURE OF SPEECH

: an expression (as a metaphor or euphemism) that substitutes a variation in point of view by which one thing or notion is referred to as if it were different in some way (as in identity, degree, shape) from what it actually is or seems to be but so related that the expression successfully implies an intended meaning or effect either slightly or greatly different from what is literally said (as “the apple of my eye”, “forever chasing rainbows”, “she didn't go to the party because she had nothing to wear”, “a pretty pickle”)