Check it out -- the singer gave feminist icon Rosie the Riveter a sexy twist with that classic red headband, but instead of her famous overalls, she was in a bedazzled barely-there American flag bikini top.

From the lyrics, Katy's all about celebrating women's achievements and feeling lucky to live in a "Woman's World" as per the title -- but as for the video ... it's nothing but pure sexiness on display.

As you can see, she's giving us up-close bouncing cleavage shots with some sexy dance moves in just that short 15-second snippet -- so you can bet the full video dropping on July 11 will turn up the heat even more.

KP's been hyping up her new single, all in the name of uplifting women, of course. But, the collab with Dr. Luke has raised some eyebrows, given the sexual misconduct allegations Kesha made against him.

Katy was even seen dodging questions about the choice to work with him while in Paris -- and Kesha seemed to jab her over it by wearing a "LOL" shirt during a gas station photo shoot.