A simile is the comparison of one thing to another, usually something of an entirely different category—in other words, a figurative comparison. For example, ''Honesty is like pregnancy; either you is or you ain't'' or ''My love is like a red, red rose.'' A simile almost always uses the word like. But a simple comparison does not make a simile. If you said that the Kennedy tax cuts of the 1960s were like the Reagan tax cuts of the 1980s, that would not be a simile.
To be effective, a simile must strike a responsive chord in the audience or make a point relevant to the subject. The honestypregnancy comparison is humorous, if a bit gray-bearded, but it does make a point: You cannot be ''a little bit honest'' any more than you can be ''a little bit pregnant.'' Although similes are often humorous, a simile does not have to be funny to be good.