The Amazonian icon Wonder Woman has been a part of DC Comics for decades, so her character has gone through a lot of retcons and updates—and the origin was no exception. During DC's 1980s "Crisis on Infinite Earths" event Wonder Woman's origin was retconned once again so that now Princess Diana was named after her long-term love interest Steve Trevor's mother, Diana Trevor, who apparently died on Themyscira saving the Amazons.
In DC's current era of continuity Infinite Frontier, all past retcons are now considered canon, as the universe has acknowledged that new continuities have not erased the past from happening. With that in mind it is still meaningful for fans to know the "Infinite Earths" story of Diana Rockwell Trevor, and how her heroic actions on Themyscira made her a hero to all the Amazonians. The Roman goddess of the hunt Diana has been named as another namesake for Wonder Woman, but at the end of the day, can't she have been named after two amazingly powerful woman?
When Wonder Woman was first introduced in All Star Comics #8 the pilot Steve Trevor was inexorably linked to the character, with Steve's plan crashing on Paradise Island in Diana's introductory issue. Trevor was Diana's first glimpse of "Man's World" and the two quickly fell in love, prompting Diana to leave Themyscira. In the "Infinite Earths" era of Wonder Woman the character Steve Trevor was much older than Diana and the two didn't have a romantic relationship, while it was also retconned that before Trevor ever crash landed on Themyscira his mother Diana, a member of the Women Airforce Service Pilots, landed there first.
Diana Rockwell Trevor was first introduced in 1987's Wonder Woman Vol. 2 #11 where it was said that after fighting as an air force pilot in WWII she decided to fly one more time, test piloting a new experimental jet instead of going to Steve's 7th birthday. While in the air she was struck by lightning and saved by a group of Nereids (minor sea-goddesses) before regaining consciousness on Paradise Island. Upon waking up— in Wonder Woman Vol.2 #12—Diana sees that the Amazons are fighting the demonic multi-armed monster Cottus, who had escaped from Tartarus through Doom's Doorway. Without any hesitation, Diana jumped into battle and fought against Cottus using her hand gun, distracting him enough so that both Philippus and Menalippe were saved but not before she herself was killed by the monster.
Queen Hippolyta and the Amazons were stunned by the "madwoman's" bravery in the face of such a vicious enemy, and they gave her a full Amazonian funeral before erecting a statue of her to honor her memory. Over the years Diana become an almost mythological figure to them, and the items she was found with (an American flag and a WAFS logo) become important relics to them. When Hippolyta created Wonder Woman from magical clay, with the help of the Gods, she decided to name her after Diana Trevor, a hero to all the warriors of Themyscira.
Diana's American flag and WAFS logo—which depicted eagles wings that look very similar to WW's chest logo—became the inspiration for Wonder Woman's first costume, meaning that both her name and famous look were both inspired by Diana Trevor and her brave sacrifice. The Trevors have always been an integral part of Wonder Woman's story, but they have usually revolved around Diana's romance with Steve. While it may be surprising to some, Wonder Woman's namesake being Diana Trevor is actually an incredibly sweet and meaningful retcon that ties the Trevor's and the Amazonians even closer together. To get the full story on Steve Trevor's mother's influence on Wonder Woman be sure to go back and check out DC Comic's "Crisis on Infinite Earths" era!