The story
- Middle Dutch · derived fromoncost“expenses, overhead”
- Middle English · inherited fromuncost“additional expense”
- English todayoncost
From on- + cost, or from Middle English uncost (“additional expense”), from Middle Dutch oncost (“expenses, overhead”) (Modern Dutch onkost), equivalent to un- + cost. Cognate with German Unkosten (“expenses”).
Etymology from Wiktionary, CC BY-SA 4.0.