x ['eks] -n

  1. the 24th letter of the English alphabet
  2. a graphic representation of this letter
  3. a speech counterpart of orthographic x
  4. ten
  5. a graphic device for reproducing the letter x
  6. one designated xesp. as the 24th in order or class, or the first in an order or class that includes x, y, and sometimes z
  7. an unknown quantity
  8. something shaped like or marked with the letter X
  9. to mark with an x
  10. to cancel or obliterate with a series of x's usu. used with out
    • x-ed out the mistake
  11. cross
  12. ex
  13. experimental
  14. extra

X ['eks] -adj

  1. of such a nature that admission is denied to persons under a specified age (as 17) used before the adoption of NC-17

Xan·a·du ['za-nə-,dü, -,dyü] -n

  1. an idyllic, exotic, or luxurious place

xanth- -comb form

  1. yellow
    • xanth ene

xan·than gum ['zan-thən-] -n

  1. a polysaccharide that is produced by fermentation of carbohydrates by a gram-negative bacterium ( Xanthomonas campestris) and is a thickening and suspending agent used esp. in pharmaceuticals and prepared foods called also xanthan

xan·thate ['zan-,thāt] -n

  1. a salt or ester of any of various thio acids and esp. C 3H 6OS 2

xan·thene [-,thēn] -n

  1. a white crystalline heterocyclic compound C 13H 10O
  2. an isomer of this that is the parent of the colored forms of the xanthene dyes
  3. any of various derivatives of xanthene

xanthene dye -n

  1. any of various brilliant fluorescent yellow to pink to bluish-red dyes that are characterized by the presence of the xanthene nucleus

xan·thine ['zan-,thēn] -n

  1. a feebly basic compound C 5H 4N 4O 2that occurs esp. in animal or plant tissue, is derived from guanine and hypoxanthine, and yields uric acid on oxidation
  2. any of various derivatives of xanthine (as methylxanthine)

Xan·thip·pe [zan-'thi-pē, -'ti-] -n

  1. an ill-tempered woman

xan·thone ['zan-,thōn] -n

  1. a ketone C 13H 8O 2that is the parent of several natural yellow pigments

xan·tho·phyll ['zan(t)-thə-,fil] -n

  1. any of several yellow to orange carotenoid pigments that are oxygen derivatives of carotenes
  2. lutein

Xa·ve·ri·an Brother [zā-'vir-ē-ən-, za-] -n

  1. a member of a Roman Catholic congregation of lay brothers founded by Theodore J. Ryken in Brugge, Belgium, in 1839 and dedicated to education

xax·is ['eks-,ak-səs] -n

  1. the axis in a plane Cartesian coordinate system parallel to which abscissas are measured
  2. one of the three axes in a three-dimensional rectangular coordinate system