Definition of "plug-in"

plug-in

/ˈplʌɡ.ɪn/

adjective
not comparable
1. Designed to be plugged into an electrical power outlet or circuit.
2. Able to be extended with further components in a modular fashion.
noun
plural plug-ins
1. Anything that plugs into something.
2. (computing) A module or device that interacts with another to add a specific feature or function.
3. An electric vehicle that can be recharged from an external power source.
4. An air freshener that can be charged by connecting it to the mains power supply.
  Quotations
  They take your best bottle of Châteauneuf-du-Pape and boil it up with Satsuma peel and bits of stick, resulting in a hot sour wine and every room of the house smelling like a festive Airwick Plug-in has exploded, with the added bonus that all your best pans are now ruined. Cheers!
  2013, Rob Temple, Very British Problems: Making Life Awkward for Ourselves One Rainy Day at a Time‎, page 141
  But unlike other Glade products with the aroma being released simply by spraying it or by opening the container, this new product the "Glade Plug-In" required that the product actually be plugged into an electrical socket in order for the aroma and fragrance to get released into the air, with the slogan for its product being "Plug it in, plug it in".
  2015, Sheldon Malone, Changing the Way You Think: One-Year Devotional Unlocking the Mind with the Word of God‎
  Plus, I expect a Febreze plug-in would smell like heaven to me right now.
  2017, Poppy Dolan, The Bluebell Bunting Society‎
  I quickly picked up the dirty laundry that was scattered all around, opened the window, sprayed the room down with Febreze, changed the plug-in, and called it good.
  2021, Lori A. Bonnevier,MSW,LCSW, You Don't Have to Crush Your Ex: Hints, Hacks, and Hell-No's to Win Your Custody Evaluation‎