That's right. I say this because it is not even listed in the spell check or dictionary in it's popular Creative Suite software.
Language is important. Language is necessary to form laws and policies. Language is an easy way to 'spread the word' of values.
As words take on new meanings such as Corporate Social Responsibility or Social Entrepreneurism, their proliferation into popular culture can be assisted by designers.
Listed below are some definitions that my 'spread the word' group have assembled.
Sustainablity: The practice or process of maintaining an indefinite form of production by protecting the conditions that production depends upon.
wikipedia currently defines sustainability as: "Sustainability is a characteristic of a process or state that can be maintained at a certain level indefinitely."
The United States Environmental Protection Agency defines sustainability as: “meeting the needs of the present without compromising the ability of future generations to meet their own needs.”
If you have or work with an alternative definition please share it. Thanks.