From The Collaborative International Dictionary of English v.0.48:
Mirth \Mirth\, n. [OE. mirthe, murthe, merthe, AS. myr[eth],
myrg[eth], merh[eth], mirh[eth]. See Merry.]
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1. Merriment; gayety accompanied with laughter; jollity.
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Then will I cause to cease . . . from the streets of
Jerusalem, the voice of mirth. --Jer. vii.
34.
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2. That which causes merriment. [Obs.] --Shak.
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Syn: Merriment; joyousness; gladness; fun; frolic; glee;
hilarity; festivity; jollity. See Gladness.
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