Definitions for "Grassroots"
local or person-to-person. A typical grassroots effort might include a door-to-door education and survey campaign.
organizations or movements]. People or society at a local level, rather than at the center of major political activity.
This term includes all bodies which depend upon the involvement of citizens and have originated upon the premises of promoting collective interest on a community or regional level.
fundamental; "the grassroots factor in making the decision"
of or involving the common people as constituting a fundamental politico-economic group; "a grassroots movement for nuclear disarmament"
the ordinary people, rather than the leaders
grassroots means ordinary people or things, so in this context it means making basic changes.