plod

from The American Heritage® Dictionary of the English Language, 4th Edition

• intransitive v. To move or walk heavily or laboriously; trudge: "donkeys that plodded wearily in a circle round a gin” ( D.H. Lawrence).
• intransitive v. To work or act perseveringly or monotonously; drudge: plodding through a mountain of paperwork.
• transitive v. To trudge along or over.
• n. The act of moving or walking heavily and slowly.
• n. The sound made by a heavy step.

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. A slow or labored walk or other motion or activity.
• v. To walk or move slowly and heavily or laboriously (+ on, through, over).
• v. To trudge over or through.
• n. A puddle.
• n. the police, police officers
• n. a police officer, especially a low-ranking one.

from the GNU version of the Collaborative International Dictionary of English

• intransitive v. To travel slowly but steadily; to trudge.
• intransitive v. To toil; to drudge; especially, to study laboriously and patiently.
• transitive v. To walk on slowly or heavily.

from The Century Dictionary and Cyclopedia

• n. A puddle.
• To trudge; travel or work slowly and perseveringly; go on in any pursuit with steady, laborious diligence.
• To lag behind or puzzle upon the scent: said of hounds.
• To go or walk over in a heavy, laboring manner; accomplish by heavy, toilsome walking or exertion.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• n. the act of walking with a slow heavy gait
• v. walk heavily and firmly, as when weary, or through mud