Toner (noun)

1. A liquid or powder used in an office copier or laser printer to transfer the ink or image to paper.
2. A liquid or lotion used to restore or balance the pH of the skin after cleansing.
3. A product used to enhance or darken the color of the hair.

Origin:

From ton + -er, from latin tonus ("tone, soun.d")

Examples:

1. He replaced the toner cartridge in the printer.
2. She applied a toner to her skin after cleansing.
3. The hair toner helped to enhance her natural color.
4. The toner was used to correct the color of the image on the paper.
5. The hair toner was used to darken the blonde highlights.