Delius, Frederick, 1862-1934, English composer, of German parentage. Influenced by Grieg, Delius combined romanticism and impressionism in his music, which is characterized by rather free structure and rich chromatic harmony. From 1886 to 1888 he studied in Leipzig, where his suite Florida (1887) was first performed. His works were appreciated earlier in Germany than in his native land, but recognition in England did come in his later years. Among his finest works are the orchestral pieces Brigg Fair (1907), On Hearing the First Cuckoo in Spring (1912), and North Country Sketches (1914). The best of his six operas is A Village Romeo and Juliet (1907). Outstanding also are his choral works Sea Drift (1906); A Mass of Life (1909), with text from Nietzsche's Thus Spake Zarathustra; and Song of the High Hills (1920). He also composed chamber music, concertos, and songs. In the 1920s Delius became blind and paralyzed but continued to compose and revise with the assistance of an amanuensis, Eric Fenby. His last public appearance was in London in 1929 at a six-day festival of his works organized by Sir Thomas Beecham.

Delius is a surname. It may refer to:

• Ernst von Delius (1912-1937) - German racing car driver
• Frederick Delius (1862-1934) - English composer
• Nicolaus Delius (1813-1888) - German philologist
• Tobias Delius (b. 1964) - English jazz musician See also
• "Delius (Song of Summer)" - Kate Bush song on Never for Ever album, "Army Dreamers" single
• Eleutherodactylus delius - species of frog found in South America
• Max Delius - fictional character in the 1992 novel The Discovery of Heaven