Brass instrument taken up by those who wish to continue their musical studies, but have failed at playing the trumpet, trombone, or anything else metallic with a mouthpiece. French horn players are the butt of most jokes in band class, though they usually admit that "they deserve it."
Also commonly referred to as "the trumpet's ugly little brother."
Kate: "I play the French horn, which is a bad instrument."
Mr. Lange: "That's right, Katie."