Hillary Clinton Smiles During 'Lock Him Up' Chant Against Trump at DNC

Hillary Clinton could barely contain her glee when the Democratic National Convention erupted in a "Lock him up" chant after a pointed dig at Donald Trump ... and she appeared to revel in the karma.

The chant -- a remix of the "Lock her up" motto used by Trump and his supporters in the 2016 presidential election -- bubbled up from the crowd in Chicago and kept building ... after the former Secretary of State called out the former prez's multiple felony convictions.

While Clinton didn't address the crowd's outburst directly, she did take a moment to pause at the podium ... where she surveyed the masses, smiled and nodded as they continued.

Trump has famously fired up his base by promising to imprison Clinton over her use of a private email server during her time as Secretary of State. So, we can't say we're surprised Clinton struggled to hide her honest reaction to the new chant.

However, Vice President Kamala Harris -- who Clinton endorsed in her speech on the first night of the DNC -- has made it clear she isn't a fan of the chant ... even if it does mean turning the tables on Trump.

Harris shut down the slogan while out on the campaign trail in New York ... saying the courts will handle Trump -- who is scheduled to be sentenced next month.

As TMZ previously reported ... Trump was found guilty on 34 counts of falsifying business records, after paying porn star Stormy Daniels hush money to lie about their previous affair during his 2016 presidential campaign.

Clinton eventually pivoted focus back to Harris ... and encouraged fellow Democrats to help make history by electing Harris to the presidency in November.