Bassoon n. : A wind instrument of the double reed kind, furnished with holes, which are stopped by the fingers, and by keys, as in flutes. It forms the natural bass to the oboe, clarinet, etc.

Example:
Is the Bassoon a difficult instrument for me to switch to if I play clarinet now?

Taxonomy
bassoon, instrument, reed, Bassoon Concerto, orchestra, Heckel, Concerto, dulcian, Heckel bassoons, bassoonists, bell, boot, Double Reed, passages, oboe, bassoon reed, bore, Sonata.

Defination from the web:
bassoon) Dulcian. Oboe. The bassoon is a woodwind instrument in the double reed family that typically plays music written in ... Appearing in its modern form in the 1800s, the bassoon figures prominently in orchestral, concert band, and chamber music literature. ...