ruinous

Meanings

1. 1
   adj

   Extremely costly; so expensive as to cause financial ruin.

   They were forced to completely replace the roof at ruinous expense.

2. 2
   adj

   causing injury or blight

3. 3
   adj

   extremely harmful

4. 4
   adj

   Causing ruin; destructive, calamitous.

5. 5
   adj

   Characterized by ruin; ruined; dilapidated; as, an edifice, bridge, or wall in a ruinous state.

Etymology

From Middle English ruynous, from Old French ruinos, ruineus, from Latin ruīnōsus. By surface analysis, ruin + -ous.