Blue is the color of the sky and sea. It is often associated with depth and stability. It symbolizes trust, loyalty, wisdom, confidence, intelligence, faith, truth, and heaven. Blue is considered beneficial to the mind and body. It slows human metabolism and produces a calming effect.
1 Backlash (sociology), an adverse reaction to something that has gained prominence.  Backlash (pressure group), a UK group opposing the 2008 law criminalising possession of extreme pornography.
What is backlash in gear terms? The term backlash is defined as the amount by which a tooth space exceeds the thickness of a gear tooth engaged in mesh. It is necessary to ensure the smooth rotation of meshed gears. The following extract is from the KHK Gear Catalogue* which details the types of backlashes, the relationships between backlashes and the fundamental equations, as well as easy-to-understand illustrations of how it all works.