scan

verb

1. (transitive)To examine sequentially, carefully, or critically; to scrutinize; to behold closely.

   “She scanned the passage carefully but could not find what she was looking for.”

   “He scanned the horizon.”

   “Yet the incident did not in the least diminish my respect for my teacher. I was by nature blind to the faults of elders. Later I came to know of many other failings of this teacher, but my regard for him remained the same. For I had learnt to carry out the orders of elders, not to scan their actions.”

   “Slowly, he scanned the horizon, listening, watching for the signs he had been taught.”

   “As the 1857 to Manchester Piccadilly rolls in, I scan the windows and realise there are plenty of spare seats, so I hop aboard. The train is a '221'+'220' combo to allow for social distancing - a luxury on an XC train as normally you're playing sardines, so I make the most of it.”

2. (transitive)To examine sequentially, carefully, or critically; to scrutinize; to behold closely.

   “to scan the hard drive for errors”

3. (transitive)To look about for; to look over quickly.
4. (transitive)To look about for; to look over quickly.
5. (transitive)To create an image of something with the use of a scanner.

   “to scan a photograph”

   “to scan internal organs by means of computed tomography”

   “Pencil drawings don't scan very well.”

6. (transitive)To read with an electronic device.

   “to scan a barcode”

   “to scan a QR code”

   “In the dispute with the RMT about scanning tickets, Jackson said it was the right thing to do to pay conductors something to scan tickets. Northern pays two pence per scan, Jackson noted, adding that ticket scanning helps to cut fraud and increase staff visibility.”

7. (obsolete, transitive)To mount by steps; to go through with step by step.

   “But ere these matchless heights I dare to scan, / There is a spot should not be pass'd in vain,— / Morat ! the proud, the patriot field ! where man / May gaze on ghastly trophies of the slain,[…]”

8. (transitive)To read or mark so as to show a specific metre.

   “In such cases as these, almost any one with a good ear will "scan" the verse correctly enough without instruction. It is not proposed to give here a list of Shakspere's slurred and contracted words; […]”

9. (intransitive)To conform to a metrical structure.

   “You're right, sir, it doesn't scan very well in the English, but in the Gaelic it's sheer poetry. Have you the Gaelic?”

noun

1. A close investigation.
2. A close investigation.
3. An instance of scanning.

   “The operators vacated the room during the scan.”

   “In the dispute with the RMT about scanning tickets, Jackson said it was the right thing to do to pay conductors something to scan tickets. Northern pays two pence per scan, Jackson noted, adding that ticket scanning helps to cut fraud and increase staff visibility.”

4. The result or output of a scanning process.

   “The doctors looked at the scans and made a diagnosis.”

5. A higher-order function that applies a binary operation to a sequence of values, starting with an accumulator, and returns a new sequence with the results.