Friend (noun)

1. A person with whom one has a bond of mutual affection, typically one exclusive of sexual or family relations.
2. A person who acts as a supporter of a cause, organization, or country by giving financial or other help.

Origin:

Old english frēond 'friend, lover, relative', of germanic origin; related to dutch vriend and german freund, from an indo-european root meaning 'to love'.

Examples:

1. My best friend and I have known each other since childhood.
2. She's a good friend of mine.
3. We became fast friends after meeting at the conference.
4. He's a friend of the environment and works to promote sustainable practices.
5. The organization relies on the support of its friends to fund its programs.
6. She donated money to the cause because she's a friend of the organization.