1) Communications jack 
A telephone plug is a type of connector used to connect a telephone set to the telephone wiring inside a building, establishing a connection to a telephone network. It is inserted into its counterpart, a telephone jack, commonly affixed to a wall or baseboard. The standard for telephone plugs varies from country to country, though the RJ11 modular...
a free connector consisting of two or more contacts on a common shank
[n] - a plug for connecting a telephone
phone plug noun a plug for connecting a telephone