From Sahih Bukhari (Hadith 135):
Narrated Abu Huraira:Allah's Messenger (ﷺ) said, "The prayer of a person who does Hadath (passes urine, stool or wind) is not accepted till he performs the ablution." A person from Hadaramout asked Abu Huraira, "What is 'Hadath'?" Abu Huraira replied, " 'Hadath' means the passing of wind
Reference: Bukhari 135