The word(s) "unbeliever" appears 179 time(s) in 160 verse(s) in Quran in Abdullah Yusuf Ali translation.

(21) If We had sent unto thee a written (message) on parchment, so that they could touch it with their hands, the unbelievers would have been sure to say: "This is nothing but obvious magic!"

(22) Of them there are some who (pretend to) listen to thee; but We have thrown veils on their hearts, So they understand it not, and deafness in their ears; if they saw every one of the signs, not they will believe in them; in so much that when they come to thee, they (but) dispute with thee; the unbelievers say: "These are nothing but tales of the ancients."

(23) The leaders of the unbelievers among his people said: "Ah! we see thou art an imbecile!" and "We think thou art a liar!"

(24) The leaders, the unbelievers among his people, said: "If ye follow Shu'aib, be sure then ye are ruined!"

(25) Behold! Allah promised you one of the two (enemy) parties, that it should be yours: Ye wished that the one unarmed should be yours, but Allah willed to justify the Truth according to His words and to cut off the roots of the unbelievers;-

(26) Remember thy Lord inspired the angels (with the message): "I am with you: give firmness to the Believers: I will instil terror into the hearts of the unbelievers: smite ye above their necks and smite all their finger-tips off them."

(27) O ye who believe! when ye meet the unbelievers in hostile array, never turn your backs to them.

(28) That, and also because Allah is He Who makes feeble the plans and stratagem of the unbelievers.

(29) (O unbelievers!) if ye prayed for victory and judgment, now hath the judgment come to you: if ye desist (from wrong), it will be best for you: if ye return (to the attack), so shall We. Not the least good will your forces be to you even if they were multiplied: for verily Allah is with those who believe!

(30) Remember how the unbelievers plotted against thee, to keep thee in bonds, or slay thee, or get thee out (of thy home). They plot and plan, and Allah too plans; but the best of planners is Allah.