Plug-in and Word processor

Plug-in noun - A printed circuit that can be inserted into expansion slots in a computer to increase the computer's capabilities.

Word processor and plug-in are semantically related. In some cases you can use "Word processor" instead a noun phrase "Plug-in".

Word processor noun - An application that provides the user with tools needed to write and edit and format text and to send it to a printer.

Plug-in and word processor are semantically related. Sometimes you can use "Plug-in" instead a noun phrase "Word processor".