Wiktionary
flumpet
n. A musical instrument that blends qualities of the trumpet and flugelhorn.
Wikipedia
Flumpet
The flumpet is a hybrid brass horn instrument that shares the construction and timbre qualities of a trumpet and flugelhorn. Commonly found in jazz music, the flumpet was invented by Art Farmer and is currently in production by David Monette. The Flumpet can be heard here https://www.youtube.com/watch?v=TpWzMqmbl4I.