Debt, Debit

The words debt and debit both have origins in the Proto-Indo-European (PIE) root ghebh (to give, to receive; to hold either in offering or taking) and Latin debitum (something owed).
 
Debt
 
Latin debitum = de (away) + habere (to have); i.e., not to have something or to keep something away from someone.
 
The word dette (anything owed or due from one person to another, a liability or obligation to pay or render something to another), from Old French dete and Latin debitum, came to English around 1300. Later in the Middle Ages, the wordsmiths of the day added the ‘b’ to dette in order to retain the word’s original Latin roots. Debt, meaning the state of being under obligation to make a payment, is from the mid-14th century.
 
Also in the mid-14th century, the phrase ‘debt of the body’ referred to that which spouses owe to each other; i.e., sexual intercourse. I am tempted to ask who was keeping track of who owes what to whom? But I won’t. I was also wondering if it could be said that if someone was a little behind in their debt payments that their account would be in arrears? Sorry… couldn’t resist.
 
Debit
 
The word debit (something that is owed, a debt), from Old French debet and Latin debitum, came to English in the mid-15th century. Debit, as a bookkeeping term meaning an entry into an account of a sum of money owing, is from 1776. The verb ‘to debit’ (to charge with a debt) is from the 1680s and ‘to debit’ (to enter on the debit side of an account) is from1865. Debit card is from 1975.
 
In brief
 
What is the difference between a debt and a debit? A debt is an amount of money owed to an individual or institution. A debit is an amount of money leaving your account to purchase something.
 
Bookkeeper, by the way, is the only English word with three consecutive double letters. But I digress.
 
Reference: Online Etymological Dictionary, https://www.etymonline.com/
https://www.economicshelp.org/blog/1988/economics/what-is-the-difference-between-a-debit-and-a-debt
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