The word(s) "worst" appears 11 time(s) in 11 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) And remember We rescued you from Pharaoh's people, who afflicted you with the worst of penalties, who slew your male children and saved alive your females: in that was a momentous trial from your Lord.

(2) Have they feet to walk with? Or hands to lay hold with? Or eyes to see with? Or ears to hear with? Say: "Call your 'god-partners', scheme (your worst) against me, and give me no respite!

(3) For the worst of beasts in the sight of Allah are the deaf and the dumb,- those who understand not.

(4) For the worst of beasts in the sight of Allah are those who reject Him: They will not believe.

(5) The Arabs of the desert are the worst in Unbelief and hypocrisy, and most fitted to be in ignorance of the command which Allah hath sent down to His Messenger: But Allah is All-knowing, All-Wise.

(6) "Other gods as partners! so scheme (your worst) against me, all of you, and give me no respite.

(7) Then shall We certainly drag out from every sect all those who were worst in obstinate rebellion against (Allah) Most Gracious.

(8) Say: "If any men go astray, (Allah) Most Gracious extends (the rope) to them, until, when they see the warning of Allah (being fulfilled) - either in punishment or in (the approach of) the Hour,- they will at length realise who is worst in position, and (who) weakest in forces!

(9) So that Allah will turn off from them (even) the worst in their deeds and give them their reward according to the best of what they have done.

(10) But We will certainly give the Unbelievers a taste of a severe Penalty, and We will requite them for the worst of their deeds.