expression, suffix
Attaches to nouns, counters, or verbs to express 'each time', 'every', or 'per'. With time/distance nouns it means 'at intervals of'. With verbs it means 'each time one does'.
この電車は10分ごとに出ます。
This train departs every 10 minutes.
彼は会う人ごとに挨拶する。
He greets each person he meets.
季節ごとに違う花が咲く。
Different flowers bloom each season.