\Slug\, n. [OE. slugge slothful, sluggen to be slothful;
cf. LG. slukk low-spirited, sad, E. slack, slouch, D. slak,
slek, a snail.]
1. A drone; a slow, lazy fellow; a sluggard. --Shak.
2. A hindrance; an obstruction. [Obs.] --Bacon.
3. (Zo["o]l.) Any one of numerous species of terrestrial
   pulmonate mollusks belonging to Limax and several related
   genera, in which the shell is either small and concealed
   in the mantle, or altogether wanting. They are closely
   allied to the land snails.
4. (Zo["o]l.) Any smooth, soft larva of a sawfly or moth
   which creeps like a mollusk; as, the pear slug; rose slug.
5. A ship that sails slowly. [Obs.] --Halliwell.
         His rendezvous for his fleet, and for all slugs to
         come to, should be between Calais and Dover.
                                               --Pepys.
6. [Perhaps a different word.] An irregularly shaped piece of
   metal, used as a missile for a gun.
7. (Print.) A thick strip of metal less than type high, and
   as long as the width of a column or a page, -- used in
   spacing out pages and to separate display lines, etc.
{Sea slug}. (Zo["o]l.)
   (a) Any nudibranch mollusk.
   (b) A holothurian.
{Slug caterpillar}. Same as {Slugworm}.

\Slug\, v. i.
To move slowly; to lie idle. [Obs.]
      To slug in sloth and sensual delight.    --Spenser.

\Slug\, v. t.
To make sluggish. [Obs.] --Milton.

\Slug\, v. t. [imp. & p. p. {Slugged}; p. pr. & vb. n.
{Slugging}.]
1. To load with a slug or slugs; as, to slug a gun.
2. To strike heavily. [Cant or Slang]

\Slug\, v. i.
To become reduced in diameter, or changed in shape, by
passing from a larger to a smaller part of the bore of the
barrel; -- said of a bullet when fired from a gun, pistol, or
other firearm.