Archaic KJV Word
Usury
Modern equivalent: interest
What Was Lost
The blanket biblical prohibition on profiting from lending. When Exodus banned usury, it banned all interest on loans to the poor -- not just high rates. The semantic narrowing to 'excessive interest' effectively repealed the biblical economic ethic by redefining the offense. What the Bible prohibited, the dictionary permitted by changing the word.
Closest Survivor in Modern English
usurious (still carries negative connotation but only for extreme rates)
Peak Usage (1611)
KJV Exodus 22:25 -- 'Neither shalt thou lay upon him usury'; Matthew 25:27 -- 'Thou oughtest to have put my money to the exchangers, and then at my coming I should have received mine own with usury'
Died ~1900
Shifted from 'any interest charged on a loan' (Latin usura 'use/interest') to 'excessively high interest,' allowing moderate interest to escape the moral scrutiny the Bible applied to all lending-for-profit.
What Replaced It
“interest”
Neutral and expected; usury carried moral weight -- charging any amount for the use of money was the issue
“loan-sharking”
Criminal extreme; usury applied to all interest, not just predatory rates
“excessive interest”
Implies moderate interest is fine; the biblical prohibition was broader