Okay, as long as we're getting technical--changing the rod length does not affect the stroke. That's determined by the crankshaft configuration. Replacing or modifying the crankshaft in order to change the stroke then requires that the rod length be altered accordingly. If the stroke is shortened, the rod needs to be lengthened in order to preserve the compression ratio. Boring out the cylinders (and using larger pistons to fit), as Spaw mentioned previously, is a logical companion procedure to achieve the desired oversquare situation, where the cylinder bore measurement exceeds the stroke measurement.

I agree with Spaw, one routinely hears about 2-stroke vs. 4-stroke engines, but I've never heard "2-stroker" or "4-stroker." wilco48 is correct in noting that "eight banger" means "eight cylinder," etc.