A caretaker is someone who supports a person physically or emotionally. The person he or she takes care of may or may not be a member of the family. This usage of the word is mainly in the United States and Canada, and less common in other countries.
In British English the term is carer.
This term can also be used for people who tend and upkeep a property, land or buildings, in the stead of the owner. It may be temporary or permanent depending on the situation.
Caretaker can also be an adjective to describe something or someone as being temporary.
The verb form is caretake and the noun for the action is caretaking.
A caregiver is a synonym for caretaker in the sense of giving support to another person. It is also a North American term and less common in other countries.
Examples
For the first time in years, the clock in the church steeple overlooking Main Street, is without a caretaker. [CBS New York]
A carer who stole thousands of pounds from pensioners and hospital patients until her life of crime was revealed when she was caught in the act on CCTV has been jailed. [The Argus]
The Financial Industry Regulatory Authority is working to issue guidance to brokers about when they should delay financial transactions over concerns a client may have dementia, be otherwise incapacitated or over them being unduly influenced by a caregiver or other person. [The Wall Street Journal]