Friend was used as a verb as early as the 13th century, but it fell out of use until recently. The popularity of social networking sites such as Facebook gave the verb friend new meaning. If you add someone to your social network, you are friending that lucky soul. Removing someone from your network can be called unfriending. Unfriend is another word that's existed in English since the 13th century when it was used as a noun to mean "an enemy."