Emily Dickinson Lexicon

SNICK'ER, or SNIG'GER, v.i. [Sw. niugg, close. This can have no connection with sneer. The elements and the sense are different.]

To laugh slily; or to laugh in one's sleeve. [It is a word in common use in New England, not easily defined. It signifies to laugh with small audible catches of voice, as when persons attempt to suppress loud laughter.]