The word "pearlest" is a superlative form of the adjective "pearly", which means resembling pearls in color, brightness, or smoothness. Some synonyms for "pearlest" include most pearly, shiniest, glossiest, sparkling, gleaming, lustrous, iridescent and bright. "Most pearly" is a straightforward replacement for "pearlest", while "shiniest" and "glossiest" emphasize the reflective quality of pearl-like surfaces. "Sparkling" and "gleaming" connote a brightness that catches the eye, while "lustrous" and "iridescent" suggest a radiant quality. "Bright" is a more generic synonym that still captures the idea of a light-reflecting surface. Overall, these synonyms offer a range of colorful options for describing the characteristic luster of pearls.