Greatly valued; precious:
(Obs.) High; lofty
(--- Informal) Excited or euphoric:
Having a high proportion of fuel to air
Negative, unfavorable, or disapproving:
Find another word for costliest. In this page you can discover 6 synonyms, antonyms, idiomatic expressions, and related words for costliest, like: dearest, steepest, highest, worthiest, poorest and richest.