Laugh and laugh and stuff.

Laughter is an ABB word, similar to:

Cheerful, shiny, dark, shiny, golden,

Delicious, quiet, dark, water, good,

Black, heavy, angry, white, black,

Loneliness, haste, green, white, all together,

Laughter, burning, excitement, warmth, green,

Red, green, cold, slow, lazy,

Noisy, dark, bright, empty, cold,

ABB-type words refer to words whose second and third words are the same. It is usually divided into three categories: adjectives, quantifiers and verbs.

In addition to ABB's words, there are ABAB's words, such as meaning, mutual benefit and so on.

References:

Baidu encyclopedia _ABB's words