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Illegal Alien
Also written: Illegal alien, Illegal aliens
avoid-as-noundehumanizing-termpolitically-contested
At a glance
Source-by-source
“Terms avoided/questioned by immigrants rights activists: alien · an illegal · anchor baby · ex-pat · failed asylum seeker · illegal alien · illegal asylum seeker · illegal immigrant · legal alien · legal citizen · legal resident · legalized … resident alien …”
SumOfUs places "illegal alien" in the column of terms immigrants' rights activists avoid or question, alongside "alien," "an illegal," and "illegal immigrant." The preferred column favors "undocumented immigrant."
“Terms and Phrases to Avoid: alien · an illegal · anchor baby · ex-pat · failed asylum seeker · illegal alien · illegal asylum seeker · illegal immigrant · legal alien · legal citizen · legal resident · legalized · migrant · natural, naturalized · resident alien”
Sierra Club lists "illegal alien" in its "Terms and Phrases to Avoid" for immigration coverage, grouped with "alien," "an illegal," and "illegal immigrant."
“Avoid. Alternative terms are undocumented worker or undocumented immigrant. … Many find the term offensive and dehumanizing because it criminalizes the person rather than the actual act of illegally entering or residing in the United States.”
The Diversity Style Guide marks "illegal alien" Avoid, recommending "undocumented worker" or "undocumented immigrant" instead, and notes the term is widely found offensive and dehumanizing because it criminalizes the person rather than the act. It cites the 1994 Unity convention statement and the 2021 USCIS shift away from "alien."
“Problematic Terms: illegals, illegal immigrant, alien, illegal alien. Preferred Terms: undocumented immigrant, unauthorized immigrant, immigrant without legal status. The bottom line: The term "illegal" is dehumanizing and unfairly replaces complex legal circumstances with an assumption of guilt.”
Where SumOfUs and Sierra Club only file the term on an avoid list, Define American offers the page's broadest set of replacements — three of them, down to "immigrant without legal status" — and states the reasoning the others leave implicit: "illegal" substitutes an assumption of guilt for the actual, complicated legal facts.
Synthesis
Every source avoids “illegal alien.” It combines the chapter’s two most-rejected moves at once, calling a person “illegal” and calling them “alien,” and the sources object to both. The Diversity Style Guide marks it “Avoid” because it “criminalizes the person rather than the actual act.” Define American files it among problematic terms and calls “illegal” dehumanizing, an “assumption of guilt.” SumOfUs and Sierra Club both place the whole “illegal/alien” family on their avoid lists. The prescribed replacement across all four is “undocumented immigrant” (or “undocumented worker”).
What sets this term apart from its components is the length of the record against it, journalistic and federal. The National Association of Hispanic Journalists campaigned against “illegal alien” and “illegal immigrant” from the mid-2000s. The AP Stylebook stopped using “illegal” for a person in 2013, which the Immigrant Defense Project and Define American both reference. In 2021 USCIS itself moved to drop “alien” and “illegal alien” in favor of “noncitizen,” “undocumented noncitizen,” or “undocumented individual.” The term began as defined statutory language and the federal government eventually retired it.
Agreement accumulated steadily. Objection built from journalist associations (mid-2000s) to wire-service style (2013) to the immigration agency’s own usage (2021), so that by the mid-2020s the rejection holds across advocacy and institutional registers alike. The 2021 USCIS shift was a Biden-era policy-manual update; a later administration reinstated “alien” in 2025, so the 2021 move marks a documented turn in agency usage rather than settled current practice. No source in the corpus offers a context in which the term is appropriate.
Audience notes
- Journalists and editors. Avoid the term entirely; use “undocumented immigrant” or “undocumented worker.” This tracks the NAHJ campaign (mid-2000s), AP style (2013), and the 2021 USCIS update (since reversed in 2025).
- Advocates and internal comms. The phrase fuses two dehumanizing moves into one; don’t repeat it even to rebut it. Describe people by circumstance and status instead.
- Legal and technical writing. Where a statute uses “alien” as a defined legal term, quote or cite it precisely, but don’t carry “illegal alien” into your own narration.
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