Learn how to say Mains correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word mains:
the mains the main distribution network for water, gas, or electricity
the mains the place where the supply of water, electricity, or gas enters a building ⇒ If you’re given warning of a flood, turn off the electricity, gas, and water at the mains.
the mains the point in a wall where you can connect electrical equipment to the power supply ⇒ Make sure plugs are disconnected from the mains.