Some yellow facts from the web:
Hope and Happiness: Yellow is sunshine. It is a warm color that, like red, has conflicting symbolism. On the one hand it denotes happiness and joy but on the other hand yellow is the color of cowardice and deceit.
Nature of Yellow: Yellow is one of the warm colors. Because of the high visibility of bright yellow, it is often used for hazard signs and some emergency vehicles. Yellow is cheerful.
Culture of Yellow: For years yellow ribbons were worn as a sign of hope as women waited from their men to come marching home from war. Today, they are still used to welcome home loved ones. Its use for hazard signs creates an association between yellow and danger, although not quite as dangerous as red. If someone is yellow it means they are a coward so yellow can have a negative meaning in some cultures.
Language of Yellow: The use of yellow in familiar phrases can help a designer see how their color of choice might be perceived by others, both the positive and negative aspects.
Yellow ribbon - hope, support, remembrance
Mellow yellow - laid back, relaxation Bad yellow
Yellow or Yellow streak or Yellow-bellied - cowardice or coward
Yellow journalism - irresponsible reporting
Yellow Words: These words are synonymous with yellow or represent various shades of the color yellow.
Lemon, yellow ocher, golden, saffron, cream, topaz, mellow yellow.