I think it is best defined from popular Twitter user: @yung_porkchop22 as he replied to a tweet from his timeline

Question for the guys:
Will you allow your daughter to marry a guy like you??

i’d pay for the wedding
by ogrizz December 17, 2018
Something conveying raw untamed power with no limits. Typically used in a humorous sense to refer to a strange situation
"Dude I saw a guy eat a completely whole watermelon without even slicing it. The absolute mad lad ate an entire watermelon"

Damn, that's some big dick energy right there
by SovietMario August 12, 2018
Sexy confidence that is unmarked by hate or struggles.

Releasing a song collaborating with one of the biggest acts of K POP when antis ask you to quit your group.
Kim Jongdae is bursting with big dick energy in his collaboration with Dynamic Duo.
by The Nobelleprize January 20, 2020
Big Dick Energy is having a small dick and NOT putting a lift kit on your F-250. It is confidence in yourself and your limitations, without acting like a douche bag.
Bill: Look at me! Look at my ridiculously large vehicle! I am amazing and will run anyone off of the road in my awesome lifted diesel engine truck. Please don't ever look at my penis! Eat my huge cloud of jet-black exhaust, pussy! I've never pleased a woman in bed or otherwise in my life!

Greg: Wow, what a douche. That guy does NOT exude Big Dick Energy
by Tweetgamestupid July 17, 2018
Did you see that Ohio State coach Ryan Day cleaned house of the terrible defensive coaches? That dude has Big Dick Energy.
by FinnaGetDisPipe January 7, 2019
Basically being a badass, anyone can have big dick energy it is not exclusive to people with a dick. Also known for short as BDE
by idkwhattocallmyself.777 November 11, 2019