jot or tittle
The smallest change. "Jot," derived from the word for the Greek letter "iota," is a small amount, while a "tittle" is the dot over a lowercase i. Make sure you run every jot or tittle by the boss first. We can't afford to lose any money on this deal.
jot or tittle
The slightest change. In the King James version of Matthew 5:18 we read, “For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.” A “jot” was an iota, a very small quantity (we still use the expression “not one iota of truth”); a tittle was a tiny accent mark. Accordingly, to have said “not one jot or tittle” was a very erudite way of refusing to make even the most minor alteration.