Adding The Delete Option To The Right Click Contextual Menu?

Solution 1:

The simplest way is to create your own Service and call it whatever you want to name it.

I created a service simply called Delete Now and put it in my context menu like I have done here:

Make Your Own Delete Service

1. Open up Automator (/Applications/Utilities/Automator) and create a new Service
   
2. At the top right pane, select files or folders in Finder
   
3. On the left most pane, select Utilities and drag the Run Shell Script option to the workflow
   
4. Change the "Pass input" field to arguments
   
5. Pase the following into the shell script body

for f in "$@"
do
rm -rf "$f"
done
afplay "/System/Library/Components/CoreAudio.component/Contents/SharedSupport/SystemSounds/finder/empty trash.aif"  

6. Click File > Save on the menubar and give you service a name. Whatever you name it, is what it will be called

This will enable it immediately on your system. If you ever decide you don't want it, and need to replace this item, navigate to ~/Library/Services/ and you will see a list of folders called {servicename}.workflow. To remove the one you don't want, just delete it then in Terminal type

killall Finder

This will restart the Finder and remove it from the context menu straight away. Otherwise, it will clear up on next restart.

Add Keyboard Shortcut

To make a keyboard shortcut for the Service you created, follow these steps:

1. From the Desktop, click the word Finder in the top left hand corner of the screen, then go to Services > Services Preferences
2. Scroll down the list on the right until you find the service you created by name. In this example, you can see Delete All that I made earlier. Highlight it, and click on add shortcut.
3. This will bring up a box. Make sure your mouse cursor is in there and depress the keys that you want to use to set the shortcut. In my example, I have used the combination Control+Shift+L.
4. Press Show All to save your settings.

Keyboard Symbols

To help anyone new to Apple keyboard symbols, here they are as follows:

^ = Control
⇧ = Shift
⌘ = Command
⌥ = Alt/Option

Solution 2:

There is a service called Delete Immediately

(through https://superuser.com/questions/10676/permanently-deleting-files-on-mac-os)

or you can make your own with Automator by means of the rm shell command.

Check also here.