COCOON
cocoon
(noun) silky envelope spun by the larvae of many insects to protect pupas and by spiders to protect eggs
cocoon
(verb) wrap in or as if in a cocoon, as for protection
cocoon
(verb) retreat as if into a cocoon, as from an unfriendly environment; “Families cocoon around the T.V. set most evenings”; “She loves to stay at home and cocoon”
Source: WordNet® 3.1
Etymology
Noun
cocoon (plural cocoons)
The silky protective case spun by the larvae of some insects in which they metamorphose, the pupa.
Any similar protective case, whether real or metaphorical.
Verb
cocoon (third-person singular simple present cocoons, present participle cocooning, simple past and past participle cocooned)
(transitive) To envelop in a protective case
(intransitive) To withdraw into such a case.
Source: Wiktionary
Co*coon", n. Etym: [F. cocon, dim. of coque shell of egge and
insects, fr. L. concha mussel shell. See Conch.]
1. An oblong case in which the silkworn lies in its chrysalis state.
It is formed of threads of silk spun by the worm just before leaving
the larval state. From these the silk of commerce is prepared.
2. (Zoöl.)
(a) The case constructed by any insect to contain its larva or pupa.
(b) The case of silk made by spiders to protect their eggs.
(c) The egg cases of mucus, etc., made by leeches and other worms.
Source: Webster’s Unabridged Dictionary 1913 Edition