\Cost"ly\ (k?st"l?; 115), a. [From Cost expense.]
1. Of great cost; expensive; dear.
         He had fitted up his palace in the most costly and
         sumptuous style, for the accomodation of the
         princess.                             --Prescott.
2. Gorgeous; sumptuous. [Poetic.]
         To show how costly summer was at hand. --Shak.