Self-neglect
Definition or reference in Statutory Guidance
Care and Support Statutory Guidance, chapter 14

Care and Support Statutory Guidance 14.17 Self-neglect This covers a wide range of behaviour neglecting to care for one's personal hygiene, health or surroundings and includes behaviour such as hoarding. It should be noted that self-neglect may not prompt a section 42 enquiry. An assessment should be made on a case by case basis. A decision on whether a response is required under safeguarding will depend on the adult's ability to protect themselves by controlling their own behaviour. There may come a point when they are no longer able to do this, without external support.
Definition or reference in Statutory Guidance
Care and Support Statutory Guidance, Annex J (Glossary)

Where someone demonstrates lack of care for themselves and or their environment and refuses assistance or services. It can be long-standing or recent.
Data descriptor
ASC Collections Data Dictionary (Beta v1.3)

Covers a wide range of behaviour; neglecting to care for one's personal hygiene, health or surroundings and includes behaviour such as hoarding.
Definition
SCIE

Types of self-neglect:
Lack of self-care to an extent that it threatens personal health and safety
Neglecting to care for one's personal hygiene, health or surroundings
Inability to avoid self-harm
Failure to seek help or access services to meet health and social care needs
Inability or unwillingness to manage one's personal affairs