- easy to understand or transparent.
- when water is said to be crystal clear, you can see through it from top to bottom.
- instructions that can be easily understood or are as straightforward as possible.
- a thing or image that is thoroughly clean or clear.
- communication or information that is easily understood and is neither vague nor ambiguous.
- The pictures on the high-definition TV are crystal clear.
- The cloudless sky on the mountaintop is crystal clear and makes it easy to view the land below.
- This package must be dropped off by 5 p.m. Is that crystal clear?
- Residents of the town have made it crystal clear that the proposed highway must not be built.
- A good lecturer’s lessons are crystal-clear, but those of a better lecturer are engaging as well.
- The instructions for preparing the dish are crystal clear.
The first known record of the idiom “crystal clear” dates back to the 1500s. It originates from the Greek word krýstallos, which means “ice.” It also refers to a type of clear rock. In Greek, the word krystaíneinn means to freeze. On the other hand, the word clear, which has been in use since the 1200s, means “easy to understand” or “transparent.”
“Clear as crystal” has been used since biblical times. In Revelation (21:11), the city of Jerusalem is said to have had the glory of God, and its light was like a precious stone, jasper, which is crystal. Many medieval poets also often used the idiom in their ballads.
By the late 1800s, when Charles Dickens and Arthur Conan Doyle respectively used it in “Edwin Drood,“1870, and “The Resident Patient, 1893, it had become a cliché. When used as a modifier before a noun, crystal clear is usually hyphenated.