Relating to a symphony, which is a long piece of music played by an orchestra.
Symphonic can make people think of big, beautiful music played by many people.
Examples:
The symphonic music was very loud.
I like to listen to symphonic music.
The symphonic orchestra played a big show.
The symphonic sound was so big, it made my ears hurt!
In the forest, the birds sang a symphonic song.
The symphonic concert was the best thing I ever heard.