Lumpier is an adjective that describes something that is uneven, bumpy, or rough. Some synonyms for lumpier include more rugged, rougher, lumpier, coarser, more irregular, uneven, lumpy, and knobbly. These words can be used interchangeably with lumpier to evoke a similar sense of texture or surface quality. Other synonyms for lumpier might include words like bumpier or choppier, which describe a more pronounced sense of physical roughness. Regardless of which synonym is used to describe something as lumpier, the effect is generally one of a surface that is not uniform or even, but rather rough and somewhat uncomfortable to touch.