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scan (skăn)
Share:
v. scanned, scan·ning, scans
v.tr.
1.
a. To look at carefully or thoroughly, especially in search of something; examine: The sailor scanned the horizon for signs of land.
b. To look over quickly or read hastily: I scanned the newspaper while eating breakfast.
2. Computers To search (stored data) automatically for specific data.
3.
a. To direct a finely focused beam of light or electrons in a systematic pattern over (a surface) in order to reproduce or sense and subsequently transmit an image.
b. To direct a radar beam in a systematic pattern across (a sector of sky) in search of a target.
4. To encode (text, for example) in digital format by means of an optical scanner.
5.
a. Medicine To direct x-rays or other energy at (a body or body part) in order to produce an image, as with a CT scanner.
b. To pass (luggage, for example) through a detector at a security checkpoint in order to detect weapons or banned materials.
6. To analyze (verse) into metrical patterns.
v.intr.
1. To analyze verse into metrical patterns.
2. To conform to a metrical pattern: Does this line scan?
n.
1. The act or an instance of scanning: my scan of the files.
2. Medicine
a. The action or process of scanning a body or body part.
b. An image produced by scanning.

[Middle English scanden, scannen, to scan a verse, from Latin scandere, to climb, scan a verse; see skand- in the Appendix of Indo-European roots.]

scanna·ble adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.