Definition
Plain language
The first digit of a number.
Also called: first digit
Why it matters: It is often the most informative single position in a number, since knowing it immediately narrows the range a value can fall in.
For example, the leading digit of 4,271 is 4.
Heard on the show
“1 Pro gives up the first digit with perfect accuracy.”Episode 246 — 160 Perfect Refusals, And The Refusals Were The Leak