Superlative form of yellow: most yellow.(adjective)
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Use "yellowest" in a sentence
"Aga toast, the yellowest egg, little beaded covers on jugs of milk and juice."
"As I pedal, smiling Colombians laugh at the tall gringo in the biggest, yellowest helmet they've ever seen, panting and purple-faced as the altitude takes its toll: Bogotá is the world's third-highest capital city, at 2,640m above sea level."
"Some bolder ones would resurface for a second glimpse, checking out dinner possibilities, and of course, these gourmands were the biggest, with the beadiest eyes and the yellowest teeth."