The word(s) "worthless" appears 3 time(s) in 3 verse(s) in Quran in Muhammad Habib Shakir translation.

(1) O you who believe! do not make your charity worthless by reproach and injury, like him who spends his property to be seen of men and does not believe in Allah and the last day; so his parable is as the parable of a smooth rock with earth upon it, then a heavy rain falls upon it, so it leaves it bare; they shall not be able to gain anything of what they have earned; and Allah does not guide the unbelieving people.

(2) And give to the orphans their property, and do not substitute worthless (things) for (their) good (ones), and do not devour their property (as an addition) to your own property; this is surely a great crime.

(3) He sends down water from the cloud, then watercourses flow (with water) according to their measure, and the torrent bears along the swelling foam, and from what they melt in the fire for the sake of making ornaments or apparatus arises a scum like it; thus does Allah compare truth and falsehood; then as for the scum, it passes away as a worthless thing; and as for that which profits the people, it tarries in the earth; thus does Allah set forth parables.