one who is obliged to do menial work; a drudge
"From running errands to washing up, prepare to be treated like a general dogsbody. Some interns dislike being treated like serfs and quit after a few days." Jo on GraduatesAnonymous.com, February 2, 2011
About the Word:
Sailors who were fed pease pudding dried peas boiled in a bag nicknamed the dish dog's body, perhaps because of its shape. Later dogsbody was a nickname applied to midshipmen, who, being junior officers, did more than their share of drudgery.