名詞 slug:

1. a projectile that is fired from a gun
   同義詞：bullet
2. an idle slothful person
   同義詞：sluggard
3. any of various terrestrial gastropods having an elongated slimy body and no external shell

動詞 slug:

1. strike heavily, especially with the fist or a bat
   同義詞：slog, swig
2. be idle; exist in a changeless situation
   同義詞：idle, laze, stagnate

1. My daughter screamed when she saw a slug.
   我的女兒看見了一條鼻涕蟲，尖叫了起來。

slug 4

v.intr.（不及物動詞）
slugged,slug.ging,slugs
To wait for or obtain a ride to work by standing at a roadside hoping to be picked up by a driver who needs another passenger to use the HOV lanes of a highway.
等搭便車，等共乘車：希望能搭上便車而站在路邊，等待需要另一位乘客以便使用公路專用車道的司機
n.（名詞）
A commuter who slugs.
等搭便車的人，等共乘車的人

來源：
Probably from slug 2
Probably from slug 2