Today I came across two different sites that contained definitions of terms commonly used in activist circles. Nezua on The Unapologetic Mexican had this list of definitions meant to decrease the number of incidences when time is wasted in conversations because someone is unaware of what someone means when they use a term in reference to another individual. If you're familiar with his blog, he also has a glosario of terms commonly found on his site in particular. Both of these links are quite informing and amusing.
The Colours of Resistance website has a list of Real Definitions that makes for a very good reference page for those who are new to anti-oppression activism. I wish I had found this page when I was struggling to understand terms that other people (in conversations) used without considering the fact that most people are unfamiliar with their meaning. They even address the use of acronyms that really make some people's writing inaccessible to those who are just being introduced to many of these concepts.
Reading the Colours of Resistance definition for Ableism motivated me to write to them with regards to their use of the term "able-bodied". This is a complicated issue, partly because people with disabilities have differing ideas about how they'd like to be referred to by others, so there are no universal terms one should use. Some terms are perfectly acceptable in certain places but considered disrespectful in others. People with disabilities deserve to have their preferences respected and if you're not sure what they prefer, then they should be asked.
The term "disablism" is often used in the same way as "ableism". In short, ableism and disablism describe the way that people with disabilities are discriminated against and, like racism, it is a systemic problem that can only be dealt with through complete changes in the way that societies function.
Both terms are considered valid in most of the people with disabilities communities that I've been a part of over the years. People tend to decide which one they'll use based on their own personal preference or which ever one is preferred in that particular community.
Also, the term "able-bodied persons" is considered problematic by many of us in the people with disabilities sphere. It has a lot to do with the notion that only those without disabilities are "able" and, therefore, that those with disabilities are not able to function as well. However, with the proper equipment, many of us are just as able-bodied as everyone else.
For example, a person with Muscular Dystrophy might not be able to make it down a long country road by foot. However, with a wheelchair, they could use their body to travel that distance even faster than those who do not have MS. We don't say that those who use cars are not able-bodied nor should we say this about those who use wheelchairs or canes or seeing eye dogs. For these reasons, the term "non-disabled" is much less problematic than "able-bodied" when one is referring to those who are not a part of the people with disabilities community.