How to remove an icon from Unity Dash?

Dash picks up its entries from .desktop files placed in /usr/share/applications and ~/.local/share/applications.

Deleting the .desktop file corresponding to your program should remove its entry from Dash.

I had the same issue, this seems to be quite a common problem. Ubuntu should include a MENU editor by default.

First I uninstalled the application, then I deleted all references from the following folder:

/usr/share/applications
/usr/local/share/applications
~/.local/share/applications

Rebooted....but never resolved my issue.

So installed this MENU editor:

sudo add-apt-repository ppa:caldas-lopes/ppa
sudo apt-get update
sudo apt-get install ezame

and delete unwanted icons.