to dominate harshly and unfairly (as in "oppressive government")
to deny equal rights to others or make them suffer (as in "The government oppresses minorities.")
I tell you that the hour is come, when we must rally round one another as One united power, and crumble into dust the oppressors that too long have battened upon the plunder of our families, upon the sweat of our brows, upon the labour of our hands, upon the strength of our sinews, upon the Godcreated glorious rights of Humanity, and upon the holy and eternal privileges of Brotherhood!’
Oh, my prostrate friends, with the galling yoke of tyrants on your necks and the iron foot of despotism treading down your fallen forms into the dust of the earth, upon which right glad would your oppressors be to see you creeping on your bellies all the days of your lives, like the serpent in the garden — oh, my brothers, and shall I as a man not add, my sisters too, what do you say, now, of Stephen Blackpool, with a slight stoop in his shoulders and about five foot seven in height,…
There are no more uses of "oppress" identified with this meaning, but check unspecified meaning below.
But, ring after ring was coiled upon the barrel of the windlass safely, and the connecting chains appeared, and finally the bucket with the two men holding on at the sides — a sight to make the head swim, and oppress the heart — and tenderly supporting between them, slung and tied within, the figure of a poor, crushed, human creature.
A secret sense of having failed and been ridiculous — a dread of what other fellows who went in for similar sorts of things, would say at his expense if they knew it — so oppressed him, that what was about the very best passage in his life was the one of all others he would not have owned to on any account, and the only one that made him ashamed of himself.