Answer: plodder

AnswerCrossword Clue
PLODDERLaborious pedestrian
PLODDERDrudge.
PLODDERSlow worker.
PLODDERHard worker.
PLODDERHard-working, so-so student
plodderone who plods (to walk heavily)
plodderto work slowly and steadily
plodderto walk heavily