Other forms: slugs
A slug is a soft creature like a snail with no shell. Slugs in the garden, a slug trail, slug pellets.
It is a snail that has lost the shell over evolutionary time, and several groups did it separately. The slime is remarkable stuff, both glue and lubricant depending on the pressure applied. A slug is also a bullet and a shot of drink. Note that the word first meant a lazy person.
1nounslugA soft shell-less creature like a snail.
“Slugs ate all the lettuces in my garden overnight.”
slug is an animal.
Middle English slugge meant a lazy person. The animal was named for its slowness, and sluggish comes from the same root.
Proto-Indo-European
*sliǵ-ōn
Middle English
slugge — lazy person", also "sloth, slothfulness
English, today
slug
Built from
Originally referred to a slow, lazy person, from Middle English slugge (“lazy person", also "sloth, slothfulness”), probably of either Old English - or Old Norse - origin; perhaps ultimately from Proto-Indo-European sliǵ-ōn, from sley- (“smooth; slick; sticky; slimy”) or otherwise from the root of Old Norse slókr (“lazy person, oaf”), whence Icelandic slókur (“laziness”). Compare nrn slug (“lazy, slothful, sluggish”), dialectal Norwegian slugg (“a large, heavy body”), sluggje (“heavy, slow person”), Danish slog (“rascal, rogue”). Compare also Dutch slak (“snail, slug”). a doublet of slotch. The sense of a hitchhiking commuter is from the sense of a counterfeit bus token. Bus operators considered sluggers to be cheating as if they were using counterfeit tokens.
Etymology from Wiktionary, CC BY-SA