„Social withdrawal is an umbrella term referring to an individual’s voluntary self-isolation from familiar and/or unfamiliar others through the consistent display of solitary behaviors“

(Barzeva, Meeus & Oldehinkel, 2018)

„The Japanese word hikikomori has long and widely been used in its verb form – hikikomoru – within Japanese society. Hikikomoru is a compound verb made up of the two characters for ‘to pull back’ [hiku] and ‘to seclude oneself’ [komoru]. Collectivism is strongly rooted in Japan and this allows for an easy formation of groups, but when a situation arises where an individual has left the group and is isolated, they are described as ‘that person who has withdrawn into seclusion!’ [hikikomotta; i.e., the past tense of hikikomoru]. In this way, individuals who have withdrawn from the group, in particular school or the workplace, for days, weeks, or months, spending most of the day within their home, are referred to in Japan as hikikomori. Hikikomori became widely used as a noun in the latter half of the 1990s when a Japanese psychiatrist, T. Saito, published ‘Hikikomori – Adolescence Without End.’ Saito tentatively defined hikikomori as a person who has ceased to go to school or work for more than 6 months and has stayed at home for most of this time.“

(Kato, Kanba & Teo, 2019)