When banks process your largest transactions first and your smallest ones last. This process only happens when you don't have enough money in your bank and the bank delays your smaller pending transactions to screw you in the asshole with insufficient funds fees.
Dude 1: "Fuck dude! My bill came through today and so did all the money I spend over the weekend!"
Dude 2: "That was like 4 days ago! Fucking overdraft rip off!"
Dude 1: "Tell me about it... that burger ended up costing me $40..."
The amount by which withdrawals exceed deposits, or the extension of credit by a lending institution to allow for such a situation.
PRETTY MUCH WHEN ONE OF THE BANK'S WORKERS IS STEALING YOUR MONEY.
MC Hammer: It seems i have overdrafted in my account.
Banker: It seems that your 1 bedroom apertment's rent was more than $500.
The one day where all your pending bank transactions go through before you can deposit or transfer money to cover them.
Duder 1: "Fucking school loan payment, grocery store, vet bill payment and my dinner out Saturday night all went through today! I got like three overdraft fees son! I'm broke!"
Duder 2: "You fucked up."
Duder 1: "Damn I want to choke somebody. Fuck this day of overdrafts."
The meal you eat when you don't have any cash money til Fri, the bank won't let you get any cash out but your card will let you buy some things on chip/pin.
You - I thought you said you didn't have any money but you're going to MackieD's?
Me - I don't but i can get an overdraft burger.