(sometimes figurative) To haul or drag along (especially something heavy); to carry; to pull.
Why do you always lug around so many books?
To run at too slow a speed.
When driving up a hill, choose a lower gear so you don't lug the engine.
To carry an excessive amount of sail for the conditions prevailing.
To pull toward the inside rail ("lugging in") or the outside rail ("lugging out") during a race.
The process by which something is lugged from one place to another; a laborious carrying or dragging.