The gloves were off as Republican presidential nominee Donald Trump and Democratic opponent Hillary Clinton faced off in their third and final debate Wednesday at the University of Nevada, Las Vegas.

Here are five memorable moments from the showdown:

>> PHOTOS: Trump vs. Clinton in final debate

1. Trump won't say whether he'll accept the election results if he loses. In the wake of Trump's recent claims that the race is being "rigged," the moderator, Fox News' Chris Wallace, asked the businessman whether he'd accept the voting results should he lose.

“I will look at it at the time,” Trump said. “I’m not looking at anything now; I will look at it at the time. What I’ve seen – what I’ve seen is so bad. First of all, the media is so dishonest and so corrupt, and the pile-on is so amazing. The New York Times actually wrote an article about it, but they don’t even care. It’s so dishonest, and they've poisoned the minds of the voters. But unfortunately for them, I think the voters are seeing through it.”

Wallace responded: “There is a tradition in this country – in fact, one of the prides of this country – is the peaceful transition of power and that no matter how hard-fought a campaign is, that at the end of the campaign, that the loser concedes to the winner. Not saying that you are necessarily going to be the you loser or the winner, but that the loser concedes to the winner and that the country comes together in part for the good of the country. Are you saying that you are not prepared now to commit to that principle?”

>> Trump on whether he'll accept election results: 'I'll keep you in suspense'

“What I’m saying now is that I will tell you at the time," Trump said. "I will keep you in suspense, OK?”

Clinton weighed in, calling Trump's answer "horrifying."

"You know, every time Donald thinks things are not going in his direction, he claims whatever it is is rigged against him," she said, throwing in a jab about how he once tweeted that the Emmys were rigged against his show, "The Apprentice." ("Should have gotten it," he shot back.)

She continued, "You know, President Obama said the other day when you're whining before the game is even finished, it just shows you're not up to doing the job."

>> Watch the moment here

2. "Bad hombres." While laying out his plans to combat illegal immigration, Trump used a phrase that sparked a lot of conversation on social media.

"One of my first acts will be to get all of the drug lords, all of the bad ones; we have some bad, bad people in this country that have to go out," he said. "We're going to get them out; we're going to secure the border. And once the border is secured, at a later date, we'll make a determination as to the rest. But we have some bad hombres here, and we're going to get them out."

>> Click here to watch the video

Naturally, "bad hombres" soon became a trending topic on Twitter ...

... and later spawned memes about the "ombre" hair trend.

>> 'Bad hombres' is the first trending meme of the final debate

3. Who's the real puppet? A heated discussion about Russian President Vladimir Putin quickly devolved into a name-calling match, much to the delight of Twitter users.

"Look, Putin, from everything I see, has no respect for this person," Trump said of Clinton.

She shot back, "Well, that's because he'd rather have a puppet as president of the United States."

"No puppet, no puppet," Trump replied as Clinton continued, "And it's pretty clear ..."

"You're the puppet," Trump interjected.

"It's pretty clear you won't admit ..." Clinton started again.

"No, you're the puppet," Trump said.

"... that the Russians have engaged in cyberattacks against the United States of America, that you encouraged espionage against our people, that you are willing to spout the Putin line, sign up for his wish list, break up NATO, do whatever he wants to do, and that you continue to get help from him, because he has a very clear favorite in this race," Clinton finished.

Memes once again flooded social media.

>> Here's the transcript of the third presidential debate

4. "Nasty woman." The candidates couldn't resist trading jabs again near the end of the evening when the topic turned to Social Security.

"I am on record as saying that we need to put more money into the Social Security Trust Fund. That's part of my commitment to raise taxes on the wealthy. My Social Security payroll contribution will go up, as will Donald's, assuming he can't figure out how to get out of it," Clinton said, referring to a New York Times report that Trump could have legally gotten out of paying federal income taxes for nearly two decades based on a leaked 1995 return.

"But what we want to do is to replenish the Social Security Trust Fund," she continued, as Trump fired back, "Such a nasty woman."

>> Click here to watch

Viewers took to social media to sound off.

>> Did Trump launch Trump TV during the last debate?

5. Hands off. At the beginning of the painfully awkward second debate, Clinton and Trump didn't greet each other with the customary handshake but eventually locked hands at the end. But that tension reached a new level at debate No. 3 when the candidates avoided shaking each other's hands entirely.

>> Watch the clips here