Cocoon (noun)

1. A protective covering spun by certain insects and other invertebrates, especially silkworms, around their pupae or eggs.
2. A protective covering or shelter in which something can develop or be kept safe and secure.

Origin:

The word cocoon comes from the french word cocon, which means a protective covering. it was first used in english in the early 18th century. the word is derived from the latin word caupona, meaning a drinking house or tavern.

Examples:

1. The silkworm spins a cocoon around its pupa.
2. He felt like he was in a cocoon of warmth and security.
3. The butterfly emerged from its cocoon, ready to fly.
4. The cocoon protected the caterpillar as it transformed into a butterfly.
5. The baby was wrapped up tightly in a cocoon of blankets.