"Yu-Gi-Oh! 5D's," like all of the "Yu-Gi-Oh!" series, originated in Japan. The company 4Kids Entertainment, the official North American licensee, releases an English-language version, but makes a number of changes to the source material to fit American broadcasting standards. Nevertheless, the original Japanese title of the show is exactly the same as the North American one: "Yu-Gi-Oh! Faibu Diis," which is the Japanese way to say the English "5D's." Both Japanese and North American sources have released multiple explanations as to what the "5D's" means.
The official Japanese meaning behind "5D's" is "five dragons." The "five dragons" refers to the five central dragon monster cards of the story. The main characters, both hero and villains alike, aspire to collect all five of these dragon monster cards. Yusei once had one of these dragon monster cards, but his friend Jack stole it from him.
"ICV2" perhaps erroneously confirmed in 2008, that the "5D's" stands for "five duel scoop." The source from which "ICV2" got the information was a Japanese entertainment magazine called "V-Jump." In Japanese, below the logo for "5D's," the magazine wrote, "Faibu Dueru Skuupu," which is the Japanese way to write "five duel scoop." However, the magazine intended the "five duel scoop" to be a clever headline to indicate that they had the news "scoop" on the new show. The "duel" referenced the duels in which "Yu-Gi-Oh!" characters often engage.
Commercials, advertisements and official releases from 4Kids Entertainment sometimes subtitle "Yu-Gi-Oh! 5D's" as "Yu-Gi-Oh! 5 Dimensions." 4Kids Entertainment explained that the "five dimensions" refers to the multiple dimensions through which the "Yu-Gi-Oh!" duelists travel as they battle their card monsters. "Five dimensions" is not the Japanese explanation of the "5D's."