A person whom one knows, likes, and trusts, A person with whom one is allied in a struggle or cause; a comrade, 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, verb_ transitive, obsolete To act as a friend to, to befriend; to be friendly to, to help, transitive To add (a person) to a list of friends on a social networking site; to officially designate (someone) as a friend

One appointed or authorized to act for another, especially a person appointed to vote as one wishes at a meeting, The agency of a substitute; the office or authority of one who is deputed to act for another, An agent or substitute authorized to act for another person, verb_ To serve as a proxy for, networking To function as a server for a client device, but pass on the requests to another server for service, intransitive verb_ rare To act or vote by proxy; to do anything by the agency of another, adjective_ Used as a proxy or acting as a proxy

A protocol that sends a message to another computer and waits for acknowledgment, often used to check if another computer on a network is reachable, A high-pitched, short and somewhat sharp sound, a sharp high-pitched resonant sound (as of a sonar echo or a bullet striking metal), verb_ sound like a car engine that is firing too early, To send an email or other message to someone in hopes of eliciting a response, networking A packet which a remote host is expected to echo, thus indicating its presence

the act of connecting computers into network, the act of working using computer network, the act of meeting new people in a business or social context, verb_ Present participle of network