The outlet will still work if you connect the circuit wires to the wrong terminals, but the polarity will be backward. When this happens, a lamp will have its bulb sleeve energized instead of the small tab inside the sockets.

Can a dimmer switch be wired backwards?

It doesnt matter if you reverse the two switch wires to a single-pole dimmer. In most cases, the two switch wires will be some color other than green or white, usually black. But one of the wires may be white if your house is wired with plastic-sheathed cable.