The Brief: BDE stands for "big dick energy."

DEEP DIVE
BDE refers to an air of confidence that someone exudes. It is not directly about the size of one’s penis, but is a metaphor used to signify that someone has the self-assurance of a well-endowed man. BDE is the opposite of cockiness or toxic masculinity.
The term was coined online in 2018 by Twitter user @imbobswaget in reference to Anthony Bourdain:
we’re talking about how anthony bourdain had big dick energy which is what he would have wanted
— vampire workday (@imbobswaget) June 9, 2018
Pete Davidson has been labeled as a quintessential possessor of BDE.
Pete davidson is 6’3 with dark circles, exudes big dick energy, looks evil but apparently is an angel, and loves his girl publicly the only thing wrong w him is that he’s a scorpio but anyway…..id married him within a month too
— Tina Ngo (@AI_hunny) June 23, 2018
Men and women can have BDE. According to the internet, Rihanna, Diplo, Idris Elba, and Cate Blanchett all have BDE.