NOUN (1)

1. the dull explosive noise made by an engine;


VERB (1)

1. make a dull, explosive sound;
- Example: "the engine chugged down the street"

WordNet (r) 3.0 (2006):

chug
    n 1: the dull explosive noise made by an engine
    v 1: make a dull, explosive sound; "the engine chugged down the
         street"

The Jargon File (version 4.4.7, 29 Dec 2003):

chug
 vi.

    To run slowly; to grind or grovel. ?The disk is chugging like crazy.?


The Free On-line Dictionary of Computing (30 December 2018):

chug

    To run slowly; to grind or grovel.  "The disk is
   chugging like crazy."

   [Jargon File]

   (1995-03-25)