Decorative style (3,4)
I believe the answer is:
art deco
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">decorative style</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for art deco that I've seen before include "Nineteen twenty's and thirties style" , "Architecture and design movement of the 1930s" , "Style of decorative art popular in 1920s and 1930s" , "1920s and 1930s ornamental style" , "Style characterised by bold geometric shapes" .)