The word(s) "lost" appears 36 time(s) in 36 verse(s) in Quran in Abdullah Yusuf Ali translation.

(11) Those to whom We have given the Book know this as they know their own sons. Those who have lost their own souls refuse therefore to believe.

(12) lost indeed are they who treat it as a falsehood that they must meet Allah,- until on a sudden the hour is on them, and they say: "Ah! woe unto us that we took no thought of it"; for they bear their burdens on their backs, and evil indeed are the burdens that they bear?

(13) lost are those who slay their children, from folly, without knowledge, and forbid food which Allah hath provided for them, inventing (lies) against Allah. They have indeed gone astray and heeded no guidance.

(14) They said: "Our Lord! We have wronged our own souls: If thou forgive us not and bestow not upon us Thy Mercy, we shall certainly be lost."

(15) Do they just wait for the final fulfilment of the event? On the day the event is finally fulfilled, those who disregarded it before will say: "The messengers of our Lord did indeed bring true (tidings). Have we no intercessors now to intercede on our behalf? Or could we be sent back? then should we behave differently from our behaviour in the past." In fact they will have lost their souls, and the things they invented will leave them in the lurch.

(16) In order that Allah may separate the impure from the pure, put the impure, one on another, heap them together, and cast them into Hell. They will be the ones to have lost.

(17) It was not fitting for the people of Medina and the Bedouin Arabs of the neighbourhood, to refuse to follow Allah's Messenger, nor to prefer their own lives to his: because nothing could they suffer or do, but was reckoned to their credit as a deed of righteousness,- whether they suffered thirst, or fatigue, or hunger, in the cause of Allah, or trod paths to raise the ire of the Unbelievers, or received any injury whatever from an enemy: for Allah suffereth not the reward to be lost of those who do good;-

(18) One day He will gather them together: (It will be) as if they had tarried but an hour of a day: they will recognise each other: assuredly those will be lost who denied the meeting with Allah and refused to receive true guidance.

(19) They will in no wise frustrate (His design) on earth, nor have they protectors besides Allah! Their penalty will be doubled! They lost the power to hear, and they did not see!

(20) They are the ones who have lost their own souls: and the (fancies) they invented have left them in the lurch!