costly Definition

costly
adj costlier, costliest

1. Involving much cost; expensive.

Thesaurus: expensive, valuable, dear, precious, lavish, opulent, splendid, excessive, steep, exorbitant; Antonym: cheap.
2. Lavish; sumptuous.
3. Involving major losses or sacrifices.

Thesaurus: disastrous, catastrophic, ruinous, harmful, damaging.

Derivative: costliness
noun