cornist

As an adjective corniest

is superlative of corny.

As a noun cornist is

a performer on the cornet or horn.

As nouns the difference between cornish and cornist

is that cornish is the inhabitants of Cornwall, especially native-born while cornist is a performer on the cornet or horn.

As a proper noun Cornish

is the Celtic language of Cornwall, related to Welsh and Breton.

As an adjective Cornish

is of or pertaining to Cornwall, a county of southwest England.

As nouns the difference between cornist and hornist

is that cornist is a performer on the cornet or horn while hornist is someone who plays the horn (the musical instrument).