| 1. | costing much; expensive; high in price: a costly emerald bracelet; costly medical care. |
| 2. | resulting in great expense: The upkeep of such a large house is costly. |
| 3. | resulting in great detriment: It was a costly mistake because no one ever trusted him again. |
| 4. | of great value; very valuable; sumptuous. |
| 5. | lavish; extravagant. |