To cause (a person, his sides) to quiver with laughter or mirth. Also of a person, to shake one's sides, to be convulsed with laughter.

To throw into a violent fit of laughter. (Associated with 1 and 2.)

transitive. To disconcert, upset, disturb; to excite; spec. (originally U.S.) to convulse with laughter. Also intransitive. colloquial.

figurative; esp. To overwhelm with delight, to convulse (someone) with laughter. Cf. kill, v. 6a.

In hyperbolic use: To come near to killing. To overwhelm (a person) by a strong impression on the mind, as of admiration, astonishment, alarm…

To impress, excite, amuse greatly. U.S. slang.