noun
three minutes
Standard time duration of three minutes. The reading さんぷん is a regular sound change from さん (three) + ふん (minute).
ここから駅まで歩いて３分です。
It's a three-minute walk from here to the station.
あと３分で電車が出ます。
The train will leave in three minutes.
Means 'three hours', a longer duration.
Means 'three seconds', a shorter duration.
Compound of 三 (さん, 'three') and 分 (ふん, 'minute'), with regular sequential voicing (連濁) changing ふん to ぷん.