Eugo wrote:And now for something completely different. The nonsensical expression that I spy is "you have a balance on your account". Nonsense, because it now means "you don't have a balance on your account". An account has a balance if credit and debit balance out to a cent. I can only guess how "balance" went from "the sides are of equal weight" to "the difference between the sides".
The etymology of the word balance is "From Middle French balance, from Late Latin *bilancia, from (accusative form of) Latin bilanx (“two-scaled”), from bi- + lanx (“plate, scale”)." i.e. the "initial" meaning was a set of scales with two plates... most of the meanings that followed refer in some way to comparing the weight or import of things. Sometimes we're interested in whether things are equal, sometimes we're interested in the difference between them.
Wikitionary has 11 (!) different definitions for the noun form of balance; here are a select four:
Wikitionary wrote:1. (uncountable) a state in which opposing forces harmonise; equilibrium
6. (uncountable) the overall result of conflicting forces, opinions etc.; the influence which ultimately "weighs" more than others
The balance of power finally lay with the Royalist forces.
I think the balance of opinion is that we should get out while we're ahead.
8. (accounting) a list accounting for the debits on one side, and for the credits on the other.
9. (accounting) the result of such a procedure [in definition 8]; the difference between credit and debit of an account.
I just need to nip to a bank and check my balance.
It's definition 9 that is common when talking about the balance of a bank account. Switching to verbs, balancing the books (trying not to spend more money than you've got coming in) is also fairly common, though in colloquial terms the preference is not to get the two to match exactly - people usually like to spend less than is going out so that they're making a profit or building up a cash reserve! I did work experience at an accountantancy firm and while all the debits and credits in the accounts book had to add up to the same numbers (or the computer would reject it), usually the actual final bank balance was one of those figures. If your firm has spent £100 on something and received £150 in payment, there will be £50 either cash in hand or sat in the bank account.