Only one word can explain the vast sums of taxpayer money that new reports show Mayor Bill de Blasio wasted on unneeded, defective or undelivered COVID supplies: corruption.

The City this week notes that Blas & Co. flushed away $225 million — i.e., nearly a quarter of a billion dollars — on medical equipment and safety gear. Now the surpluses are getting auctioned off for a mere $500,000, about 0.2 cents for every buck spent.

Sure, the pandemic’s unknowns early on required officials to err on the side of having too much, not too little — and moving fast to get it. That’s why both the city and the state suspended normal oversight and vetting rules.

Yet Team Blas didn’t simply overbuy; it used COVID as an excuse to discard all responsibility for spending taxpayer money.

As city Comptroller Brad Lander reveals in another report, agencies still had a legal duty to do background checks on venders and ensure supplies they bought were “reasonably priced.” Too often, they didn’t. So much of what they purchased was not only overpriced, but of “poor quality,” “defective” or never even delivered.

The city, for example, paid $6.70 each for 50,000 face shields when the average market price was just $3.67. Sub-par masks ran $4 each, instead of $3.10 for good ones.

And a huge giveaway is the dealing with Digital Gadgets, whose owner Charlie Tebele was a major Blas donor. It got one $9.1 million contract to deliver ventilators; it never did. Instead, the company was allowed to substitute N95 masks.

Recall that the same company got a similar no-bid deal from Gov. Kathy Hochul (who also got big Tebele donations): $637 million for test kits at twice the per-kit price Californians paid.

Senate Majority Leader Andrea Stewart-Cousins is giving Hochul a pass on her smelly Tebele deal, but she can’t block a probe of the city’s scandals. What other companies got overpriced, unneeded contracts from Blas — and how much did their owners fork over to him? Is that $224.5 million in “waste” all of it? From March to June 2020 alone, Lander says, city COVID deals totaled more than $1.5 billion.

Between Gov. Andrew Cuomo’s deadly failure on nursing homes, schools that were closed far too long, and Mayor de Blasio’s colossal waste of money, New York’s COVID response may be the worst in the nation.