Noun. 1. achromatic color-a color lacking hue; white or grey or black. achromatic colour. color, coloring, colouring, colour-a visual attribute of things that results from the light they emit or transmit or reflect; a white color is made up of many different wavelengths of light.
A good candidate for a mail host is a system that connects your systems to the outside world or to a parent domain. 1  Become superuser on the mail host system. 2  Verify the host name configuration. 3  Update. Create an entry for the new mail host in the appropriate hosts file.  Change the correct configuration 1  file. Restart and test your mail configuration.
Related words. 1  host verb. 2  host computer noun. 3  host at hostess.  1. [countable] someone who invites people to a meal or party, or to stay in their 1  home. 2. [countable] someone who introduces and talks to the people taking part in a television or radio programme a game show/chat show host.