tug-v; 3 Senses

Sense Number 1: Pull or strain hard at something without carrying.

Commentary: Includes: TUG AT

The prisoner tugged at the chains.
This movie tugs at the heart strings.
Each oar was tugged by several men.

VerbNet: carry-11.4,hold-15.1-1,push-12-1,touch-20-1
FrameNet: Manipulation,Cause_motion
PropBank: tug.02,tug.03
WordNet 3.0 Sense Numbers: 1, 6

Sense Number 2: Strive and make an effort to reach a goal or to prevent something.

We have to tug a little to make the deadline!
She is tugging away at her thesis.
She tugged and wrestled with her conflicts.

VerbNet: NM
FrameNet: NP
PropBank: NM
WordNet 3.0 Sense Numbers: 2, 7

Sense Number 3: Carry with difficulty, perhaps by using a tug boat.

I tugged the freighter into the harbour.
You'll have to tug this suitcase up the stairs.
The horse finally tugged the cart out of the mud.

VerbNet: carry-11.4,push-12-1,split-23.2,touch-20-1
FrameNet: Cause_motion
PropBank: tug.01
WordNet 3.0 Sense Numbers: 3, 4, 5