(onomatopoeia) A sound mimicking the loss of air, as if someone's solar plexus had just been struck.
(slang) Synonym of ouch (“expressing sympathy at another's pain, shock at a high price, etc.”).
noun
A sound made in pain, as when expelling air after being struck.
(Internet) Something cringeworthy, or which arouses disappointment, often used in conjunction with the qualifier big.
noun
(UK, slang, dated) Money.
“Oh,” Johnnie was saying, “so Quest is his name, is it, and he lives in a city called Boisingham, does he? Is he an oof bird?” (rich)
“Rather,” answered the Tiger, “if only one can make the dollars run, but he's a nasty mean boy, he is.
What's he after? Oof—oof—oof, that's what he's after. He's for his own pocket, he's for being boss of all the woolly West. He's after keeping us poor and making himself rich.