Can I map a character onto the keyboard?

I want to add the "therefore" symbol, "∴", to my regular keyboard layout. Can I do this? I have searched the forums in vain for an answer. This character is not among the standard symbols that can be accessed via the keyboard viewer.

For example, I would like to be able to map the ∴ symbol to a key combination like, ⌥ + w, for example. Currently, the ⌥ + w combination is mapped to the sum symbol, ∑.