How to make macOS Terminal window Transparent (or Opaque)

The Terminal of macOS is opaque by default, if you wish to make it transparent, you need to follow the below steps,

1. Open Terminal,
2. Go to Menu: Preferences...,
3. Now Choose the theme that you are using, it should be the Basic theme by default,
4. Under Background: Click on the image box that reads - Color and Effects,
5. You will see a Colors window open, where there are multiple bars, adjust Opacity, as you make this value less then 100% you will see that the background of the Terminal window gets transparent.
6. Close the Colors window,
7. Close the Preferences window
8. The changes must be reflected now.

If you want to revert the changes, you follow the same steps and change the opacity to 100%, so the Terminal window will look opqaue.