Secret Service Code Names of 11 U.S. Presidents | Britannica

Lancer
John F. Kennedy’s code name was apt, given that his administration was often compared to Camelot, the magical court of Arthurian legend of which Lancelot was a legendary knight. First Lady Jackie Kennedy was known as Lace.

Searchlight
Richard Nixon had one of the more ironic code names in light of his attempts to cover up what became the Watergate scandal.

Passkey
Gerald Ford’s moniker also held a certain irony, as he locked the door on any possibility of criminal prosecution against his predecessor, Nixon, by granting him “a full, free, and absolute pardon.”

Deacon
Jimmy Carter’s name reflected his deeply religious faith. Long active in the Baptist church, he continued to teach Sunday school after becoming president.

Rawhide
Ronald Reagan’s code name was possibly a reference to the numerous westerns he had appeared in before becoming a politician.

Timberwolf
Alas, it is unknown why George H.W. Bush was named for the largest member of the dog family.

Eagle
Bill Clinton also had an unexplained animal moniker. Some have speculated that the code name concerned his association with the Boy Scouts. Eagle Scout is the organization’s top rank, a fitting name for someone holding the highest office in the land.

Trailblazer
George W. Bush’s presidential code name was complimentary, but his name while his father was president was less flattering: Tumbler. According to some reports, it was based on his alleged propensity to party.

Renegade
Barack Obama reportedly picked this moniker from a list of code names that started with R. No word on what the other choices were.

Mogul
While Donald Trump once stated that he would select “Humble” as his code name, the Secret Service opted for something that was…well, a little less humble.

Celtic
Joe Biden’s code name—which was the same one used when he was vice president—is a reference to his Irish heritage.

I'm sure it's just a coincidence that JFK's name sounds a lot like "lance her".