friend

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A person whom one knows, likes, and trusts.
• noun A person whom one knows; an acquaintance.
• noun A person with whom one is allied in a struggle or cause; a comrade.
• noun One who supports, sympathizes with, or patronizes a group, cause, or movement.
• noun A member of the Society of Friends; a Quaker.
• transitive verb Informal To add (someone) as a friend on a social networking website.
• transitive verb Archaic To befriend.
• idiom (be friends with) To be a friend of.

from The Century Dictionary.

• noun One who is attached to another by feelings of personal regard and preference; one who entertains for another sentiments which lead him to seek his company and to study to promote his welfare.
• noun One not hostile; one of the same nation, party, or kin; one at amity with another; an ally: opposed to foe or enemy.
• noun One who is favorable, as to a cause, institution, or class; a favorer or promoter: as, a friend of or to commerce; a friend of or to public schools.
• noun Used as a term of salutation, or in familiar address.
• noun [capitalized] A member of the Society of Friends; a Quaker.
• noun A lover, of either sex.
• noun In Scotslaw, a tutor or curator.
• noun Synonyms Companion, Comrade, etc. See associate.
• noun Patron, advocate, partizan, well-wisher.
• To befriend.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb obsolete To act as the friend of; to favor; to countenance; to befriend.
• noun One who entertains for another such sentiments of esteem, respect, and affection that he seeks his society and welfare; a wellwisher; an intimate associate; sometimes, an attendant.
• noun One not inimical or hostile; one not a foe or enemy; also, one of the same nation, party, kin, etc., whose friendly feelings may be assumed. The word is some times used as a term of friendly address.
• noun One who looks propitiously on a cause, an institution, a project, and the like; a favorer; a promoter.
• noun One of a religious sect characterized by disuse of outward rites and an ordained ministry, by simplicity of dress and speech, and esp. by opposition to war and a desire to live at peace with all men. They are popularly called Quakers.
• noun obsolete A paramour of either sex.
• noun one disposed to act as a friend in a place of special opportunity or influence.
• noun to have friendly relations with.
• noun to become reconciled to or on friendly terms with.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A person other than a family member, spouse or lover whose company one enjoys and towards whom one feels affection.
• noun A boyfriend or girlfriend.
• noun An associate who provides assistance.
• noun A person with whom one is vaguely or indirectly acquainted
• noun A person who backs or supports something.
• noun informal An object or idea that can be used for good.
• noun colloquial, sarcastic Used as a form of address when warning someone.
• noun computing, programming In object-oriented programming, a function or class granted special access to the private and protected members of another class.
• verb transitive, obsolete To act as a friend to, to befriend; to be friendly to, to help.
• verb transitive To add (a person) to a list of friends on a social networking site; to officially designate (someone) as a friend.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a person you know well and regard with affection and trust
• noun a member of the Religious Society of Friends founded by George Fox (the Friends have never called themselves Quakers)
• noun an associate who provides cooperation or assistance
• noun a person who backs a politician or a team etc.
• noun a person with whom you are acquainted