As some sneaky five-year-olds know, crossing one’s fingers while making a promise is an effective way to vitiate, or destroy the validity of, an agreement.

Vitiate is often used when a legal agreement is made invalid, but it can also refer to the debasement or corruption of something or someone. If a malicious five-year-old on the playground teaches the other children to lie with their fingers crossed, she would be responsible for vitiating the playground community. The first syllable of this word is pronounced "vish," like the first syllable in vicious.

Definitions of vitiate
  1. verb
    make imperfect
    synonyms: deflower, impair, mar, spoil
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    cloud, corrupt, defile, pollute, sully, taint, tarnish
    place under suspicion or cast doubt upon
    blemish, deface, disfigure
    mar or spoil the appearance of
    mangle, maul
    injure badly by beating
    mark, pit, pock, scar
    mark with a scar
    type of:
    inflict damage upon
  2. verb
    corrupt morally or by intemperance or sensuality
    synonyms: corrupt, debase, debauch, demoralise, demoralize, deprave, misdirect, pervert, profane, subvert
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    carnalise, carnalize, sensualise, sensualize
    debase through carnal gratification
    corrupt with ideas or an ideology
    lead astray, lead off
    teach immoral behavior to
    spoil as if by poison
    bastardise, bastardize
    change something so that its value declines; for example, art forms
    incite to commit a crime or an evil deed
    type of:
    alter, change, modify
    cause to change; make different; cause a transformation
  3. verb
    take away the legal force of or render ineffective
    synonyms: invalidate, void
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    make valid or confirm the validity of
    type of:
    alter, change, modify
    cause to change; make different; cause a transformation
Word Family

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