Yea, yeah, and yay are commonly equated with the word yes. If you’re one of the people doing it, you would be correct roughly sixty-six percent of the time—you can use yea or yeah for yes, but it’s a whole different story with yay, which is the exclamation people use to express joy.
Yea vs. Yeah
Yea is pronounced “yay” and it means yes. You would typically use it only under specific circumstances, such as a formal vote. Voting yea means that you are in favor of the proposal. Even less commonly in modern speech, it can also be used instead of “indeed” or when you want to emphasize and reiterate something you just said. Yea is by no means a recent entry into the language—its origin can be traced all the way back to the Old English word gēa.
Yeah is usually classified as yes’s less formal sister. It originated around the beginning of the twentieth century, so there are no Old English words it can be traced to. But words don’t need to have roots that reach a millennium into the past for us to use them.
Yea/Yeah vs. Yay
You pronounce yay in the same way you pronounce yea, which makes these two words homophones—indistiguishable when spoken and easily confused when written. They have different meanings, though. While yea is the word we sometimes use for yes, yay is the word we use to express joy, approval, or excitement. The origins of yay are difficult to pin down—some sources say it came from yeah, others say it came from yea.