Hikikomori \hai-kee-kuh-more-ri\ , noun;
1. Abnormal avoidance of social contact; acute social withdrawl
2. A person, typically an adolescent male, engaging in this; a recluse, shut-in
This word is first attested in 1998 from Japanese hikikomori ("staying indoors, social withdrawl, a recluse"), which is a combination of hiki- + komoru ("to pull, draw, repeat" + "to shut oneself up, stay inside"). It is documented in Portuguese as fiqicomori ("to withdraw oneself, or be shut in").