Synonyms for Lumpy (same or very similar meaning)
WordNet sense 1 (like or containing small sticky lumps):
chunky
WordNet sense 2 (not shapely; not well-proportioned and pleasing in shape):
unshapely
WordNet sense 3 (not even or uniform as e.g. in shape or texture):
uneven
From the ODE community, based on WordNet
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