[1] : The Collaborative International Dictionary of English v.0.48

plod \plod\, v. i. imp.  p. p. plodded; p. pr.  vb. n.
   plodding. gf. gael. plod a clod, a pool; also, to strike
   or pelt with a clod or clods.
   1. to travel slowly but steadily; to trudge. --shak.
      1913 webster

   2. to toil; to drudge; especially, to study laboriously and
      patiently. "plodding schoolmen." --drayton.
      1913 webster
see also:
plodded plodding 

[2] : WordNet (r) 2.0

plod
     v : walk heavily and firmly, as when weary, or through mud;
         "mules plodded in a circle around a grindstone" syn: slog,
          footslog, trudge, pad, tramp
     also: plodding, plodded
see also:
slog footslog trudge pad tramp plodding 
plodded 

[3] : WordNet (r) 2.0

plodded
     see plod
see also:
plod 

Plodded >> P Words
Plodded, definition of term: Plodded
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