Definition of yellowest:
(n) :
The color of sunflower petals and lemons; the color obtained by mixing green and red light, or by subtracting blue from white light; the color evoked by light of wavelength around 580 nm; one of the three primary colors in subtractive color systems.
(n) :
(US) The middle light in a set of three traffic lights, the lighting of which indicates that drivers should stop short of the intersection if it is safe to do so.
(v) :
(intransitive) To become yellow or yellower.
(v) :
(transitive) To make (something) yellow or yellower.
(n) :
(sports) A yellow card.
(n) :
(snooker) One of the color balls used in snooker, with a value of 2 points.