The word(s) "error" appears 54 time(s) in 53 verse(s) in Quran in Muhammad Pickthal translation.

(41) And when he brought them the Truth from Our presence, they said: Slay the sons of those who believe with him, and spare their women. But the plot of disbelievers is in naught but error.

(42) Canst thou (Muhammad) make the deaf to hear, or canst thou guide the blind or him who is in error manifest?

(43) And whoso respondeth not to Allah's summoner he can nowise escape in the earth, and he hath no protecting friends instead of Him. Such are in error manifest.

(44) His comrade saith: Our Lord! I did not cause him to rebel, but he was (himself) far gone in error.

(45) For they said; Is it a mortal man, alone among us, that we are to follow? Then indeed we should fall into error and madness.

(46) Lo! the guilty are in error and madness.

(47) He it is Who hath caused those of the People of the Scripture who disbelieved to go forth from their homes unto the first exile. Ye deemed not that they would go forth, while they deemed that their strongholds would protect them from Allah. But Allah reached them from a place whereof they recked not, and cast terror in their hearts so that they ruined their houses with their own hands and the hands of the believers. So learn a lesson, O ye who have eyes!

(48) He it is Who hath sent among the unlettered ones a messenger of their own, to recite unto them His revelations and to make them grow, and to teach them the Scripture and wisdom, though heretofore they were indeed in error manifest,

(49) They say: Yea, verily, a warner came unto us; but we denied and said: Allah hath naught revealed; ye are in naught but a great error.

(50) Say: He is the Beneficent. In Him we believe and in Him we put our trust. And ye will soon know who it is that is in error manifest.