The term "lumpishly" can be replaced by a number of synonyms, depending on the context in which it is used. Some of the common synonyms for "lumpishly" include clumsily, awkwardly, ponderously, and slowly. In some cases, words such as sluggishly, lethargically, and inertly can also be used to describe actions or movements that are slow or lacking in energy. The choice of synonym will depend on the specific connotation that the writer or speaker wishes to convey. Ultimately, a good writer or speaker needs to be able to select the right synonym for the situation in order to communicate effectively and clearly.