古英语中的 myrgð 意为“快乐、愉悦、永恒的幸福、救赎”（这些原始含义现在已基本消失），源自原始日耳曼语 *murgitha（同样是中世纪荷兰语 merchte 的词源）。它是一个名词，表示一种品质，来自 *murgjo-（参见 merry；还可以参见 -th (2)）。到13世纪初，这个词的意思演变为“快乐的表现或表现形式”；到14世纪中期，又被用来指“愉悦、欢快、快乐的状态或感觉”。Mirthquake 这个词首次出现于1928年，指的是那些能引发阵阵狂笑的娱乐活动，最初是用来形容哈罗德·劳埃德的电影。
I HAVE always preferred chearfulness to mirth. The latter, I consider as an act, the former as an habit of the mind. Mirth is short and transient, chearfulness fixed and permanent. Those are often raised into the greatest transports of mirth, who are subject to the greatest depressions of melancholy: on the contrary, chearfulness, though it does not give the mind such an exquisite gladness, prevents us from falling into any depths of sorrow. Mirth is like a flash of lightning, that breaks through a gloom of clouds, and glitters for a moment; chearfulness keeps up a kind of day-light in the mind, and fills it with a steady and perpetual serenity. [Addison, "Spectator," May 17, 1712]
我一直更喜欢愉快的心情，而不是单纯的欢笑。后者在我看来是一种表演，而前者则是一种心态。欢笑短暂而易逝，而愉快则是持久而稳定的。那些容易陷入深深忧郁的人，往往会在某些时刻被欢笑冲击到极点；相反，愉快虽然不如欢笑那样瞬间强烈，却能有效防止我们陷入悲伤的深渊。欢笑就像闪电，穿透乌云，瞬间闪耀；而愉快则像心灵中的晨光，带来持续而稳定的宁静。[亚迪生，《观察者》，1712年5月17日]
