1A horizontal beam or girder that supports a structure such as a building or bridge.
橋の桁が老朽化し、補強工事が行われた。
The bridge's girders had deteriorated, so reinforcement work was carried out.
屋根を支える桁が一本折れていた。
One of the beams supporting the roof had broken.
2A digit or place value in a number (ones, tens, hundreds, ...); also used to express a difference in scale, as in 桁違い ('an order of magnitude different').
このパスワードは桁数が足りません。
This password doesn't have enough digits.
二人の年収は桁が違う。
Their annual incomes are on completely different scales.
電卓で計算したら、答えの桁を一つ間違えていた。
When I calculated it on the calculator, I was off by one digit in the answer.
売上が去年より一桁増えた。
Sales increased by a whole order of magnitude compared to last year.