Source : Webster's Revised Unabridged Dictionary (1913)

Sunburst \Sun"burst`\, n.
   A burst of sunlight.

Source : WordNet®

sunburst
     adj : pleated or tucked in lines radiating from a circular edge;
           "blouse with a sunburst yoke"; "sunray fan pleats below
           the hips" [syn: {sunray}]
     n : a jewelled brooch with a pattern resembling the sun