Sentence:  A contact device installed at an outlet for the connection of an attachment plug is a <WSD>receptacle</WSD>nb.... A multiple <WSD>receptacle</WSD> is a single device consisting of two or more <WSD>receptacles</WSD>nb.... 
Meaning of the word marked with <WSD> tags:  A contact device installed at an outlet for the connection of an attachment plug (typically by receiving the plug's prongs) to supply portable appliances or equipment.