To giggle is defined as to laugh in a silly or twinkly way.(verb)
When you give a silly little laugh, this is an example of a time when you giggle.
The definition of a giggle is a silly laugh.(noun)
A silly or nervous little laugh is an example of a giggle.
See giggle in Webster's New World College Dictionary
Origin: 16th c., prob. < Du giggelen: for IE base see gig
See giggle in American Heritage Dictionary 4
verb gig·gled, gig·gling, gig·gles verb, intransitive
Origin: Of imitative origin.
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