Sometimes called community-engaged art or community-based art, every community art project is unique in terms of who the participants are, the goal of the project, the character of the collaboration, etc.. Therefore it is not easy (or even possible?) to summarize with one definition. However, here are some descriptions offered:
The community arts movement is inspired by social justice activism and is grounded in the principle of cultural democracy. Community art is often used as a tool for stimulating dialogue, for documenting community-rooted narratives and for encouraging self-empowerment.
As a collaborative artistic process, community art brings together a group of people (who associate as a community. form a community through art or share a commonality in their identity) to contribute to artworks that they use to develop self-empowerment, beautify shared space, to share their perspectives with a wider public, or to challenge the status quo … – with and through art.
Scott Marsden (1996)
Community art is a practice that believes the production of arts a social activity that expresses people’s lived experience. Community art, by its very nature. has no common aesthetic standard. The aesthetic of this art is fundamentally grounded in its content and its culture. It is a language of self-representation or self-collaboration through which an individual or a group confirms its identity. Community can be defined as a demographic community, social community or community of interest.
– Published in: Naming A Practice: Curatorial Strategies for the Future, Walter Phillips Gallery Editions, The Banff Centre (quote on page 195).
Ontario Arts Council (1998)
… a collaborative process between a professional practicing artist and a community. It is a collective method of art-making, engaging professional artists and self-defined communities through collaborative artistic expression. It is as much about process as it is about the artistic product or outcome. …Given the breadth of its definition, community arts is sometimes difficult to distinguish from those projects that have components of community activity. What separates genuine projects from others is the nature of the collaborative process and the active, co-creative involvement of the artist and the community.
Community Arts Handbook, Ontario Arts Council, Toronto Ontario, 1998, p. 7
Kathie deNobriga and Mat Schwarzman (1999)
Community-based art is creative expression that emerges from communities of people working together to improve their individual and collective circumstances. Community-based art involves a wide range of social contexts and definitions, and includes an understanding of “communities” that includes not only geographical places, but also groups of people identified with historical or ethnic traditions, or dedicated to a particular belief or spirit
Published on the Community Arts Network website , “Community-based Art for Social Change,” 1999
Devora Neumark and Caroline Alexander-Stevens (2005)
Les arts communautaires sont avant tout un art des relations. Dans un contexte communautaire, le rapport entre l’inspiration de l’artiste et son application se construit à partir d’une interrelation avec les croyances, les pensées, les opinions, les actions et les compétences des autres personnes en jeu. Le travail de collaboration exige des artistes qu’ils soient prêts à établir une relation d’interdépendance – afin d’être en mesure d’assurer une présence intègre auprès de la communauté et dans le cadre du processus d’art communautaire. C’est là un engagement de taille.
– Caroline Alexander-Stevens et Devora Neumark. “L’art des relations : l’engagement et autres considérations concernant les arts communautaires,” in the Cahier de l’action culturelle which is published by Laboratoire d’animation et recherche culturelles (LARC) at the Université du Québec à Montréal (UQÀM): 22.
Canada Council for the Arts
Community arts projects can take many forms. Activities involve groups of people coming together—either individually or through a community partner organization—to create artistic activities or works with the help and guidance of integrated arts professional artists. These projects can involve a large or small number of people, more than one community partner or group, and other sectors (such as health, justice, education or social causes).
– Canada Council for the Arts, on line reference: “Guidelines for Integrated Arts Program: Artists and Community Collaboration ,”
Community Art is any art form which focuses on involving community members, who contribute a variety of talents, to design and create a public art piece. These projects are done together with a professional artist who passes on skills to the participants through the art-making process. The content of the artwork usually reflects local issues that have been identified by people within the community. Community art can use any art form including theatre, music, visual arts, literary arts, dance and more. The importance of the project is placed on the process of art making because of its ability to build relationships and involve all members of a neighbourhood helping to establish collective identity. The artwork, once complete, is exhibited or performed for the community. – My HRM.ca 
For other organizations that are trying to describe collaborative, community-based or community-engaged art please see: