The word(s) "liar" appears 29 time(s) in 29 verse(s) in Quran in Muhammad Pickthal translation.

(11) And when those who ascribed partners to Allah behold those partners of theirs, they will say: Our Lord! these are our partners unto whom we used to cry instead of Thee. But they will fling to them the saying: Lo! ye verily are liars!

(12) Only they invent falsehood who believe not Allah's revelations, and (only) they are the liars.

(13) Nay, but We have brought them the Truth, and lo! they are liars.

(14) Why did they not produce four witnesses? Since they produce not witnesses, they verily are liars in the sight of Allah.

(15) Thou art but a mortal like us, and lo! we deem thee of the liars.

(16) They listen eagerly, but most of them are liars.

(17) (Solomon) said: We shall see whether thou speakest truth or whether thou art of the liars.

(18) And Pharaoh said: O chiefs! I know not that ye have a god other than me, so kindle for me (a fire), O Haman, to bake the mud; and set up for me a lofty tower in order that I may survey the god of Moses; and lo! I deem him of the liars.

(19) Those who disbelieve say unto those who believe: Follow our way (of religion) and we verily will bear your sins (for you). They cannot bear aught of their sins. Lo! they verily are liars.

(20) Say (O Muhammad): Call upon those whom ye set up beside Allah! They possess not an atom's weight either in the heavens or in the earth, nor have they any share in either, nor hath He an auxiliary among them.