Antonyms of adj lumpen

1 sense of lumpen

Sense 1
lumpish, lumpen, unthinking -- (mentally sluggish)

INDIRECT (VIA stupid) -> smart -- (showing mental alertness and calculation and resourcefulness)

Similarity of adj lumpen

1 sense of lumpen

Sense 1
lumpish, lumpen, unthinking -- (mentally sluggish)
       => stupid (vs. smart) -- (lacking or marked by lack of intellectual acuity)