There is probably more motion felt forward, but there is also some aft. If you're looking for the smoothest area, that would be on a lower deck mid-ship.
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The bow (the front or pointy end for the very non-nautical) will feel more motion than the stern (the back or flat end). Midships and on a lower deck will feel the least motion. The bow is designed to plunge into waves and as a consequence will have a more pronounced pitching or up and down motion in heavy seas. Now DW and I are not prone to sea sickness, but we survived 18-20 foot seas on the Glory last fall with no problems at all. Several people we met and liked were sea sick, however.
We had cabins towards the front on the Liberty and there were several nights that we were woken up by the sound on crashing on the hull. I'm sure it was the ship hitting the waves, but it sounded like it was hitting rocks, or the anchor was clanging against the front of the ship. In any case, it made it very hard to sleep.