It means you get involved. Technically, our local forms of government are not participatory democracies. Officially, participatory democracy is direct democracy, in the sense that all citizens are actively involved in all important decisions.
It shouldn't if washed with gentle care. Rayon is a cellulose fabric and like most cellulose fabrics, it may shrink when washed. If the manufacturer has indicated the garment should be dry cleaned only, do not push your luck. If it is hand-washable though, you can use the gentle cycle on your washing machine and Woolite to get the job done.
Rayon is described as a regenerated fibre because the cellulose, obtained from soft woods or from the short fibres (linters) that adhere to cottonseeds, is converted to a liquid compound, squeezed through tiny holes in a device called a spinnerette, and then converted back to cellulose in the form of fibre.