From WordNet (r) 3.0 (2006):
tug
n 1: a sudden abrupt pull [syn: tug, jerk]
2: a powerful small boat designed to pull or push larger ships
[syn: tugboat, tug, towboat, tower]
v 1: pull hard; "The prisoner tugged at the chains"; "This movie
tugs at the heart strings"
2: strive and make an effort to reach a goal; "She tugged for
years to make a decent living"; "We have to push a little to
make the deadline!"; "She is driving away at her doctoral
thesis" [syn: tug, labor, labour, push, drive]
3: tow (a vessel) with a tug; "The tugboat tugged the freighter
into the harbor"
4: carry with difficulty; "You'll have to lug this suitcase"
[syn: lug, tote, tug]
5: move by pulling hard; "The horse finally tugged the cart out
of the mud"
6: pull or strain hard at; "Each oar was tugged by several men"
7: struggle in opposition; "She tugged and wrestled with her
conflicts"