Daniel W says:

fag 1 of 6 verb (1) ˈfag fagged; fagging intransitive verb : to work hard : TOIL transitive verb : to tire by strenuous activity : EXHAUST fagged by the strenuous climb fag 2 of 6 noun (1) 1 chiefly British : TOIL, DRUDGERY it is such a fag; I came back tired to death Jane Austen 2 : DRUDGE sense 1 fag 3 of 6 noun (2) : an English public-school boy who acts as servant to an older schoolmate fag 4 of 6 verb (2) fagged; fagging; fags intransitive verb : to serve as a fag (see FAG entry 3) especially in an English public school fagging for older boys during his first year fag 5 of 6 noun (3) : CIGARETTE fag 6 of 6 noun (4) plural fags offensive : a gay person —used as a term of abuse and disparagement