Sentence:  She was a fat, round little woman, richly apparelled in velvet and lace, […]; and the way she laughed, cackling like a hen, the way she talked to the waiters and the maid, […]&mdash;all these unexpected phenomena impelled one to hysterical <WSD>mirth</WSD>, and made one class her with such immortally ludicrous types as Ally Sloper, the Widow Twankey, or Miss Moucher. 
Meaning of the word marked with <WSD> tags:  The emotion usually following humour and accompanied by laughter; merriment; jollity; gaiety.