ruinously

Ruinously is an adverb derived from the adjective ruinous. It describes an action or condition that results in, or is likely to lead to, ruin, significant damage, or catastrophic outcome. The term is often applied to costs, prices, or penalties that are excessive beyond reasonable expectation, or to outcomes that threaten a person, organization, or plan with ruin.

The adjective ruinous derives from the noun ruin, ultimately from Latin ruina meaning collapse or downfall; English formed ruinous in the late Middle Ages, and ruinously as the adverbial form later followed.

Usage notes: Ruinously is formal enough for narrative and analytical writing but also appears in journalism and opinion pieces. It tends to convey strong judgment about financial or practical consequences, and while it is often used hyperbolically, it can reflect genuine severity in appropriate contexts.

Examples: The project ran ruinously over budget. The new regulation could prove ruinously punitive for small businesses. The contract carried ruinously high penalties for delays.