From Longman Dictionary of Contemporary Englishgrass rootsˌgrass ˈroots noun → the grass roots —grass roots adjective We are hoping for full participation at grass roots level.
Examples from the Corpus
grass roots• Fourth, don't always do a news release on all the grass roots activities.• The President continued to campaign at the grass roots.• The stereotype of toughness also flourishes at the grass roots in party circles.• But even the grass roots of the club are sprouting.• The charity is backed by staff from the grass roots to directorate level.• One had to return to grass roots. 