"Severe deprivation" refers to a very serious lack or shortage of something important, such as food, shelter, or essential necessities. It means being in a state of extreme need or deprivation. Full definition
Do the effects of early severe deprivation on cognition persist into early adolescence? (cambridge.org)
Some people with the disorder describe severe deprivation, neglect and abandonment during childhood. (bpdfamily.com)
In his maiden speech yesterday he noted that there are areas of severe deprivation in his constituency where only 8.1 % of pupils achieve 5 GCSEs — and that those pupils can expect to live for nearly 10 years less and to earn an average of # 30,000 a year less than those in the more prosperous parts of the seats: (conservativehome.blogs.com)