To illegalize something is to make it illegal, or to announce that it's against the law. When a city's police set a new curfew, they illegalize kids and teenagers being out at night.

The verb illegalize is a somewhat informal way to say "make something illegal." Your town might illegalize smoking in public places or your state senators could vote to illegalize dog fighting. In either case, something previously allowed is being made illegal. It's considered better grammar to say "make illegal," or even "criminalize," since illegalize is a relatively new verb constructed from illegal, "against the law," and the verb-forming suffix ize.

Definitions of illegalize
  1. verb
    declare illegal; outlaw
    synonyms: criminalise, criminalize, illegalise, outlaw
    see moresee less
    decriminalise, decriminalize, legalise, legalize, legitimate, legitimatise, legitimatize, legitimise, legitimize
    make legal
    ban, censor
    forbid the public distribution of ( a movie or a newspaper)
    ban the publication of (documents), as for security or copyright reasons
    type of:
    disallow, forbid, interdict, nix, prohibit, proscribe, veto
    command against
Word Family

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