The action of the verb to laugh.
"The children were laughing loudly while they played in the park."
In plain English: Laughing is the act of making funny noises when something makes you feel happy and amused.
"They were all caught up in laughing at his funny joke."
present participle of laugh
"The children were laughing loudly as they played in the park."
In plain English: Laughing is making happy sounds when something funny happens to you.
"The children were laughing at their funny game before dinner."
The word comes from Middle English lawghynge, which was formed by adding the suffix -ing to the verb laugh. Its original meaning was simply the act of laughing.