The word(s) "oppress" appears 21 time(s) in 18 verse(s) in Quran in Abdullah Yusuf Ali translation.

(11) (Deeds) after the manner of the people of Pharaoh and those before them": They treated as false the Signs of their Lord: so We destroyed them for their crimes, and We drowned the people of Pharaoh: for they were all oppressors and wrong-doers.

(12) The Unbelievers are protectors, one of another: Unless ye do this, (protect each other), there would be tumult and oppression on earth, and great mischief.

(13) They said: "In Allah do we put out trust. Our Lord! make us not a trial for those who practise oppression;

(14) To those who leave their homes in the cause of Allah, after suffering oppression,- We will assuredly give a goodly home in this world; but truly the reward of the Hereafter will be greater. If they only realised (this)!

(15) Then there are among men such as say, "We believe in Allah"; but when they suffer affliction in (the cause of) Allah, they treat men's oppression as if it were the Wrath of Allah! And if help comes (to thee) from thy Lord, they are sure to say, "We have (always) been with you!" Does not Allah know best all that is in the hearts of all creation?

(16) Each one of them We seized for his crime: of them, against some We sent a violent tornado (with showers of stones); some were caught by a (mighty) Blast; some We caused the earth to swallow up; and some We drowned (in the waters): It was not Allah Who injured (or oppressed) them:" They injured (and oppressed) their own souls.

(17) And those who, when an oppressive wrong is inflicted on them, (are not cowed but) help and defend themselves.

(18) The blame is only against those who oppress men and wrong-doing and insolently transgress beyond bounds through the land, defying right and justice: for such there will be a penalty grievous.