The United States Department of Housing and Urban Development (HUD) defines a "chronically homeless" person as "an unaccompanied homeless individual with a disabling condition who has either been continuously homeless for a year or more, or has had at least four episodes of homelessness in the past three years."

Definition

The term "homelessness" includes the people whose primary daytime residence is in an institution that provides a residence for individuals intended to be institutionalized, or in a public or private place not designed for use as a regular sleeping conditions for human beings.

Other names for homelessness

The term used to describe homeless people in academic articles and government reports is "homeless people". Popular slang terms for the homeless include: vagrant, tramp, hobo (U.S.), transient, bum (U.S.), bagman/bagwoman, street walker, urban outdoorsmen , or the wandering poor. The term '(of) No Fixed Abode' (NFA) is used in legal circumstances. Sometimes the term "houseless" is used to reflect a more accurate condition in some cases.

Contributing causes of homelessness

• Lack of affordable housing. An article in the November 2007 issue of Atlantic Monthly reported on a study of the cost of obtaining the "right to build" (i.e. a building permit, red tape, bureaucracy, etc.) in different U.S. cities. The "right to build" cost does not include the cost of the land or the cost of constructing the house. The study was conducted by Harvard economists Edward Glaeser and Kristina Tobio. According to the chart accompanying the article, the cost of obtaining the "right to build" adds approximately $700,000 to the cost of each new house that is built in San Francisco.
• Unavailability of employment opportunities.
• Poverty, caused by many factors including unemployment and underemployment.
• Lack of affordable healthcare.
• Substance abuse and unavailability or lack of needed services.
• Mental illness, such as and unavailability or lack of needed mental health services.
• Domestic violence.
• Prison release and re-entry into society.
• The mass deinstitutionalisation of the mentally ill in the Western world from the 1960s and 1970s onwards.
• Natural disaster.
• Forced eviction - In many countries, people lose their homes by government order to make way for newer upscale high rise buildings, roadways, and other governmental needs. The compensation may be minimal, in which case the former occupants cannot find appropriate new housing and become homeless.
• Mortgage foreclosures where mortgage holders see the best solution to a loan default is to take and sell the house to pay off the debt. The popular press made an issue of this in 2008; the real magnitude of the problem is undocumented.