Synonyms for Slug (same or very similar meaning)
WordNet sense 1 (an idle slothful person):
sluggard
WordNet sense 2 (a projectile that is fired from a gun):
bullet
WordNet sense 3 (be idle; exist in a changeless situation):
idle, laze, stagnate
WordNet sense 4 (strike heavily, especially with the fist or a bat):
slog, swig
From the ODE community, based on WordNet
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