Bottom-up and Grassroots

Bottom-up adjective - Of an approach to a problem that begins with details and works up to the highest conceptual level.

Grassroots and bottom-up are semantically related. In some cases you can replace term "Grassroots" with "Bottom-up", this terms are similar.

Grassroots adjective - Of or involving the common people as constituting a fundamental political and economic group.

Bottom-up and grassroots are semantically related. You can use "Bottom-up" instead an adjective "Grassroots".