Synonyms for Tug (same or very similar meaning)
WordNet sense 1 (a powerful small boat designed to pull or push larger ships):
towboat, tower, tugboat, towerWordNet sense 2 (strive and make an effort to reach a goal):
drive, labor, push, labourWordNet sense 3 (carry with difficulty):
lug, toteWordNet sense 4 (a sudden abrupt pull):
jerkFrom the ODE community, based on WordNetadd/edit