Traditional exclamations of triumph or vindication come into and go out of fashion, but they tend to beget variations, and they usually begin with one of several similar sounds, as exemplified by yay, hooray, and woo-hoo. Here’s a discussion of those terms of acclamation and others, all of which are almost invariably followed by exclamation points to signal enthusiastic delivery.
Yay is simply an alternate spelling of yeah or yea, which have distinct pronunciations and meanings. (Yeah, an informal variant of yes, is pronounced “ya” and sometimes spelled that way; yea, which sounds like yay, survives as an affirmation in biblical contexts and as a counterpart to nay in voting contexts.)
Hooray is an alternate spelling of hurrah; both go back hundreds of years, and two other, less common variants, hurray and hooray, are nearly as old. (They all stem from huzza—emphasis is on the second syllable—which dates back to the time of Shakespeare and survives only at “faires” that recreate a Renaissance environment.) These words can also refer to a cheer or a fanfare, or excitement, and the oldest sometimes denotes a disturbance, as in “There was a big hurrah about something happening down the street.”
Woo-hoo, also spelled whoo-hoo or truncated as whoo—the variation woot, sometimes spelled with zeros instead of o’s, originated in computer gaming—is very recent and has no etymological basis; it’s basically a sound effect, although it’s close in sound to whoop, which derives from the Old French term huper (also spelled houper), which means “cry” or “shout.” (Whoop is the source of whoopee, meaning “revelry,” which developed into the euphemism “making whoopee” for “having sex” and was in vogue for a time as part of the name of the whoopee cushion, a novelty device that simulates flatulence when an unsuspecting person sits on it.)
Other exclamations of triumph or delight include wahoo, whee, yahoo, yee-haw, and yippee, which all go back a century or so. (The noun yahoo, referring to a coarse, ignorant person, is unrelated; it derives from the name of a race of brutish humans in Jonathan Swift’s Gulliver’s Travels.) Hallelujah (from the Hebrew word hallĕlūyāh, meaning “Praise the Lord”) is sometimes substituted even by the nonreligious.
More recent cries of triumph include aha or simply hah, rah, and uh-huh (pronounced with a rising inflection), or simply yes with an exaggerated, elongated pronunciation of the final consonant. Boo-ya is an outdated, mercifully short-lived expression of triumph with a mocking edge.
Exclamations of opprobrium are much more limited in variety: The basic critical cry is boo (which is also an exclamation delivered suddenly when someone makes an attempt to frighten one or more others); aw is more an interjection of disappointment than one of disapproval. Criticism in contexts in which acclamations are used, such as sporting events, tend to be delivered as statements; among the more restrained are comments such as, “You’ve got to be kidding me.”