sun·burst 
(sŭnbûrst′)
(sŭnbûrst′)n.
1. A sudden burst of sunlight, as through broken clouds.
2.
a. A pattern or design consisting of a central disk with radiating spires projecting in the manner of sunbeams.
b. A jeweled brooch with such a design.
sunburstmosaic design at Palau Güell,
by Antoni Gaudí
Barcelona, Spain