Longman Dictionary of Contemporary English
Wiktionary
n. A group of nonprofessional people who support each other over a problem which all members share.
Wikipedia
In a support group, members provide each other with various types of help, usually nonprofessional and nonmaterial, for a particular shared, usually burdensome, characteristic. Members with the same issues can come together for sharing coping strategies, to feel more empowered and for a sense of community. The help may take the form of providing and evaluating relevant information, relating personal experiences, listening to and accepting others' experiences, providing sympathetic understanding and establishing social networks. A support group may also work to inform the public or engage in advocacy.
Usage examples of "support group".
His peripheral vision showed movement to his left--the support group--but no, it was a car, driving across the playground right at them--not the Suburban, something else.
She'd written to ask Bobby to find a similar support group for Wes, who had loved Ethan best out of all his brothers and sisters, and was hurt the worst by the loss.
The principle American support group of Hamas, is the IAP in Dallas, Texas.
I've been tasked to recruit B-2A flight and support crews from the active-duty ranks, among others, to support group operations.
And that didn't even count the freighters and tugs of Vice Admiral Alexandra Cole's Support Group.