Scientific name: genus: papio
A ballon is a small rubber bag that you can fill up with air or helium. Balloons stretch, and can get quite big when they are blown up.
Balloons you fill by blowing them up are very common at parties. Helium balloons go up if you let them go, and are fun to play with. Ordinary balloons go down if you let them go, not up.
A bassoon is a woodwind instrument. It typically plays in the lower registers, with a warm, dark sound. It is typically played as part of an orchestra or a smaller group that plays classical music.
A cocoon is a place a caterpillar makes for itself. The caterpillar goes to sleep inside it for some time and then comes out as a butterfly.