Trump seemed not to know what the '19' in COVID-19 stood for at a rally in Phoenix, where he also broke city rules by not wearing a mask

• President Donald Trump expressed confusion about where the "19" in COVID-19 came from during his rally in Phoenix on Tuesday night.
• "I said, 'What's the 19?' COVID-19, some people can't explain what the 19, give me, COVID-19, I said, 'That's an odd name,'" he said.
• The president also ignored a local law that mandates wearing a mask in public.
• Most of the 3,000-strong crowd also went without a mask, according to Politico.

President Donald Trump seemed confused about the origin of the "19" in COVID-19 during his rally in Phoenix on Tuesday night as he riffed on various names for the novel coronavirus.

"I could give you 19 or 20 names for that, right," Trump told the student attendees, who were gathered for a rally organized by Students for Trump.

He went on to give several examples including "kung flu," a racist term targeting China, where the virus was first identified, that perhaps received the loudest cheer from the crowd.

He continued: "I said, 'What's the 19?' COVID-19, some people can't explain what the 19, give me, COVID-19, I said, 'That's an odd name.'"

COVID-19 is the disease caused by the novel coronavirus; the name comes from "coronavirus disease 2019," the year the virus was identified.

Trump appeared without a mask on Tuesday, breaking a Phoenix rule that came into force less than 72 hours earlier.

Coronavirus cases in Arizona are at an all-time high. Nearly 1,300 deaths from the virus have been recorded in the state, according to the local news outlet the Arizona Mirror.

Starting Saturday, Phoenix residents must wear a mask anywhere indoors or outdoors where physical distancing can't be maintained. There is a $250 fine for repeat noncompliance, according to The Arizona Republic.

Mayor Kate Gallego, a Democrat, said she would not be enforcing the rule at the Trump rally, the Arizona Mirror reported.

The president has long resisted wearing a mask in public despite public-health advice to do so.

Most of the attendees at the packed event also ignored the mask rule, according to Politico. About 3,000 students showed up to watch the president.

The rally is the second on a campaign trail that started Saturday in Tulsa, Oklahoma, where Trump addressed a venue filled to about one-third capacity, far below the campaign's expectations.

Touting the event's online viewership — which his campaign says was about 4 million — Trump told the Arizona crowd it had been the "number-one show in Fox history for a Saturday night," according to Politico.