What is the abstract noun of the verb laugh?

There is no abstract noun for the verb to laugh.

The noun form of the verb to laugh is the gerund, laughing; a concrete noun as a Word for a physical act.

The noun 'laugh' is a concrete noun as a Word for a physical action or sound. The concrete noun 'laugh' can be used in an abstract context.

Example: He mistook me for a famous movie star. What a laugh!