Wingman is a role that a person may take when a friend needs support with approaching potential partners. A wingman is someone who is on the "inside" and is used to help someone with relationships. There seem to be sex differences such that females' friends help them avoid undesirable potential partners, while males' friends help them attract desirable potential mates.[1]
The 'pre-wing' refers to the talking up of one friend to another in order to build an attractive persona before any direct interactions. The pre-wing is then usually followed up by the wingman role; the follow-up support often involving befriending associates of the potential partner.
The 1986 film Top Gun employed the term, as did the 1996 film Swingers.