Flatus comes from Latin flatus ('a blowing, breath'), from flare ('to blow'). The development is chiefly a borrowing or learned continuation, carrying an older form and meaning into English rather than building the word from a purely native base. In present use, it is used as a noun meaning "gas generated in the stomach or intestines", so the historical material remains connected with the current sense rather than standing as bare ancestry. The wider English family includes related forms such as flatulence, flatulent, inflate, and deflate, showing how the same historical material continues to organize neighboring vocabulary. The named historical forms include Latin flatus and Latin flare, keeping the history tied to concrete forms rather than a loose resemblance. Its semantic neighborhood includes gas, wind, flatulence, and fart, locating the modern specialization without adding a new origin story.