expression, suffix
every ...; at intervals of ...; with ... in between
Attaches to a noun expressing a distance, time period, or number of objects to mean 'every ...' or 'at intervals of ...'. The interval includes the unit itself, so 1日おきに means 'every other day' (with one day in between).
この薬は8時間おきに飲んでください。
Please take this medicine every 8 hours.
駅までバスが10分おきに出ている。
Buses leave for the station every 10 minutes.
1メートルおきに木を植えた。
We planted trees at intervals of one meter.