grass·roots 
(grăsrts′, -rts′)
(grăsrts′, -rts′)pl.n. (used with a sing. or pl. verb)
1. People at a local or low level rather than at the center or upper levels of an organization or movement. Often used with the.
2. The lowest or most basic level of an organization or movement: a campaign that started at the grassroots.
grassroots adj.