noun
great number; very large number
Refers to a number that is extremely large, often in contrast to small numbers or in contexts like statistics or estimates.
大数の法則によると、試行回数が増えるほど確率は理論値に近づく。
According to the law of large numbers, the more trials you do, the closer the probability gets to the theoretical value.
noun
round number; approximate figure
Used when giving a rough or rounded figure, not an exact count. Often appears in business or casual estimates.
費用は大数で見積もっておいてください。
Please estimate the cost in round numbers.