(NEXSTAR) – From Las Vegas to New York City, revelers donned costumes with emerald shamrocks and four-leaf clovers to celebrate St. Patrick’s Day.

And if you thought four-leaf clovers were shamrocks, you’re not alone, but the Irish shamrock, the country’s national symbol, only has three leaves.

In 2017, Twitter users were quick to poke fun at former President Trump’s online store, which sold limited edition St. Patrick’s Day MAGA hats with a gold four-leaf clover on the back.

They might have avoided the mistake if they learned from the Obama re-election team’s similar flub leading up to St. Patrick’s Day in 2012.

Shoe giant Nike also made the mistake, emblazoning their popular Nike Air Force 1 “Shamrock” shoes in 2021 with four leaf clovers, and famed design house Hermès plastered four-leaf clovers on green, crocodile skin handbags meant to honor Ireland.

Even Guinness Canada failed to use a shamrock, opting for four leaves in a 2016 ad campaign.

The number of leaves on the shamrock has special significance in Ireland, while a four leaf clover is “a sugary, oat piece that’s usually found in a box of Lucky Charms cereal,” the Irish Independent quipped in 2017.

According to legend, the shamrock dates back to St. Patrick himself, who used it as a metaphor for the Holy Trinity.

The fourth leaf, which comes from a rare genetic mutation and symbolizes good luck for many people – but it has nothing to do with St. Patrick.