Reese Witherspoon: Dear Harvard, I'm Still Lawyer Material And Also Really Hot!!

Reese Witherspoon's briefs are still ready for presentation ... as is her sick bikini bod.

Reese marked the 15th anniversary of "Legally Blonde" by slipping back into a bunch of her wardrobe from the flick ... and wisely included the bikini she wore during that Harvard essay scene.

Erection, your honor!

Sustained!