Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class I. Words Expressing Abstract Relations
Section II. Relation
3. Partial Relation

20a. Variation.

   NOUN:VARIATION; alteration (change) [See Change].
  MODIFICATION, moods and tenses; discrepance, discrepancy.
  DIVERGENCY [See Divergence]; deviation [See Deviation]; aberration; innovation.
   VERB:VARY (change) [See Change]; deviate [See Deviation]; diverge [See Divergence]; alternate, swerve.
   ADJECTIVE:VARIED &c. v.; modified; diversified [See Nonuniformity]; dissimilar [See Dissimilarity].
  1. Variety is the very spice of life.—Cowper
  2. Age cannot wither her, nor custom stale Her infinite variety.—Antony and Cleopatra