cornet (n.) Look up cornet at Dictionary.com
c.1400, "A wind instrument made of wood and provided with six finger holes" [Middle English Dictionary], from Old French cornet (14c.) "a small horn," diminutive of corn "a horn," from Latin cornu "horn" (see horn (n.)). Modern use is short for cornet-à-pistons "cornet with pistons."
The quality of the tone is penetrating and unsympathetic, by no means equal to that of the trumpet, for which it is commonly substituted. ["cornet" entry in "Century Dictionary and Cyclopedia," 1902]