Guffaw, loud laughter, belly laugh; a joke, a hoot, a massive laugh, high comedy. Derived directly as a nominalization of the slang verb ржать (to laugh loudly/coarsely, originally meaning to neigh like a horse). In everyday speech, street slang, and internet culture, it is a highly popular masculine noun used to describe either the act of collective, uncontrollable laughter or the source of that laughter itself (вчера на тусе такой ржач был — “yesterday at the party it was a total hoot”). It is frequently used in the popular expression чистый ржач (pure comedy / just for laughs).
Гулкий ржач всех солдат, валяющихся на койках.
Loud, echoing laughter of all the soldiers lying on their bunks.
(Александр Скутин, Самые страшные войска, 2007)
