The Arabic is Haram and the Quran uses it as an inviolate and unquestioned command/order.

2: 194 The prohibited [haramu] month for the prohibited month and so for all things prohibited[harroumatu] there is the law of equality.  If then anyone transgresses the prohibition against you transgress ye likewise against him.  But fear Allah and know that Allah is with those who restrain themselves

2: 217         They ask thee concerning fighting in the Prohibited [harami] Month.  Say: "Fighting therein is a grave (offence); but graver is it in the sight of Allah to prevent access to the path of Allah to deny Him to prevent access to the Sacred Mosque and drive out its members.  Tumult and oppression are worse than slaughter.  Nor will they cease fighting you until they turn you back from your faith if they can.  And if any of you turn back from their faith and die in unbelief their works will bear no fruit in this life and in the Hereafter; they will be Companions of the Fire and will abide therein.

4: 23        Prohibited [hurrimat] to you (for marriage) are: your mother daughters sisters father's sisters mother's sisters; brother's daughters sister's daughters foster-mothers (who gave you suck) foster-sisters; your wives' mothers; your step-daughters under your guardianship born of your wives to whom ye have gone in no prohibition if ye have not gone in; (those who have been) wives of your sons proceeding from your loins; and two sisters in wedlock at one and the same time except for what is past; for Allah is Oft-Forgiving Most Merciful.

6: 151        Say: "Come I will rehearse what Allah hath (really) prohibited [harrama] you from": join not anything as equal with Him; be good to your parents: kill not your children on a plea of want;  We provide sustenance for you and for them;  come not nigh to shameful deeds whether open or secret; take not life which Allah hath made sacred except by way of justice and law: thus doth He command you that ye may learn wisdom

16: 118 To the Jews We prohibited [harramna] such things as We have mentioned to thee before: We did them no wrong but they were used to doing wrong to themselves.