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.
No, polyester should not shrink. A pure polyester shirt is the easiest thing in the world to take care of. Wash in washer and hang on a hanger to dry. It will dry quickly with no wrinkles. No need to waste energy on a dryer.