Like many holistically evolving cultural manifestations (and species), separating a new form from its predecessor with a simple definition can be difficult. So far, there is no firm consensus on what an ecovillage is.
Robert Gilman lists the following characteristics:
1. Human scale
2. Full featured settlement
3. Harmlessly integrates human activities into the natural world
4. Supports healthy human development and
5. Can be successfully continued into the indefinite future
6. Has multiple centers of initiative
The Eco-village Challenge
...of developing a community living in balanced harmony - with itself as well as nature - is tough, but attainable. Robert Gilman (1991)
Although the Gilman definition is the one most frequently used, others have emerged.
Jonathan Dawson, President of Global Ecovillage Network, in his 2006 book Ecovillages: New Frontiers for Sustainability offers the following both as a new definition (page 36), and as the common characteristics of all ecovillages (page 70).
1) Private citizens initiatives
2) in which the communitarian impulse is of central importance,
3) that are seeking to win back some measure of control over community resources,
4) that have a strong shared values base (often referred to as 'spirituality')
5) and that act as centres of research, demonstration, and (in most cases) training.
He claims that latter (5) is essential to distinguish ecovillages from similar more locally focused initiatives, "which are not in service of a wider goal." I find this distinction less than compelling.
It's hard to discern any commonalities between the Gilman and Dawson definitions.
Sustainability definitions manifest similar disparity according to Philip Sutton, who classified them into four categories.
Using his definitional types, the Dawson definition is more "a description of what the thing or action is (dictionary-style definition)", while Gilman's is "a description of what is required to bring the thing or action into being
(definition by strategy)" [or what might be termed an aspirational description]
Given this definitional complexity, when answering "What is an ecovillage" or "How do you define ecovillage", I prefer the succinctness of:
"An ecovillage is the intentional intersection of community and sustainability."
(Slightly modified from Oakland's 611Ecovillage founder Dan Antolioni. http://www.611ecovillage.com/
Rather than struggling with labeling such as San Mateo Ecovillage did with "not exactly a co-op...something between co-op, cohousing, and ecovillage", www.greensolutions.org/smcc it may be more fruitful to track ones trajectory on the community and sustainability plane -- how rapidly is one's eco-home/community moving away from the (0,0) origin that characterizes most of our society. Thus co-op, cohousing, and ecovillage, in that order would likely be rated progressively richer on the community dimension. Placement could be determined through GEN's Community Sustainability Assessment http://gen.ecovillage.org/activities/csa/ by combining the Social Checklist with the Spiritual/Cultural one. Alternatively, the Spiritual/Cultural dimension could provide a third coordinate axis.The trajectory of each site would then be mapped into this cubic region. Any placement significantly removed from the origin would be richer in 'ecovillageness'.
Along those lines, a sustainable future would be one where almost everyone lives in an ecovillage. According to Torbjörn Lahti, that is close to the situation in Sweden, where eco-municipality is no longer a significant distinction and is rarely used. Thus our eventual goal here is to make the prefix "eco" tautological. Our challenge in Chicago is to jump start that process.