Y, y

See more synonyms for Y, y on Thesaurus.com
noun, plural Y's or Ys, y's or ys.
  1. the 25th letter of the English alphabet, a semivowel.
  2. any spoken sound represented by the letter Y or y, as in yet, city, or rhythm.
  3. something having the shape of a Y.
  4. a written or printed representation of the letter Y or y.
  5. a device, as a printer's type, for reproducing the letter Y or y.


  1. yoctosecond.
Also called ys


[yok-tuh-sek-uh nd]
  1. one septillionth (10-24) of a second. Abbreviation: ysec, ys
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for ys

Historical Examples of ys

  • There ys no token of rayn: for the cloudes be both fayr and clere.

  • As here ae, and io, let them cut into halfes the right lines uy, and ys.

  • But the perpendicular uy, is equall to ys; because each of them is the double of yo.

  • For withyn London he ys next unto the kyng in all maner thynge.

    The Story of London

    Henry B. Wheatley

  • Ten such sittings and my 'King of Ys' will have its day with the world.

ys in Science


  1. The symbol for yttrium.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.