A moderate blue.
[Middle English bis, dark, gray, blue-gray (sense uncertain) , from Old French bis, dark gray (as used in such compounds as azur bis, dark blue, and vert bis, dark green); akin to Old Provençal bis and Old Italian bigio, ultimately of unknown origin.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.