1. To move or walk heavily or laboriously; to trudge with a slow heavy tread: After hours of plodding up into the mountains, James and his family were glad to start their way back down to their camp.
2. To work or act perseveringly or monotonously; to drudge: The teacher spent several hours plodding through a stack of student essays.
3. To walk heavily, slowly, and firmly, as when weary, or struggling through mud: Maurice and Lydia plodded through mud that came up over their shoes when they were near the stream.