undocumented

American  

[uhn-dok-yuh-men-tid] / ʌnˈdɒk yəˌmɛn tɪd /

adjective

1. lacking documentation or authentication.

2. lacking proper immigration or working papers: undocumented immigrants.

   an undocumented worker;

   undocumented immigrants.

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Sensitive Note

See illegal alien.

Etymology

Origin of undocumented

First recorded in 1880–85; un- ¹ + documented ( def. )

Compare meaning

How does undocumented compare to similar and commonly confused words? Explore the most common comparisons:

• undocumented vs. illegal

Example Sentences

Its unusual body structure highlights just how diverse termite species can be and points to how many organisms in tropical environments remain undocumented.

From Science Daily • Apr. 1, 2026

“Under the longstanding definition, undocumented immigrants are domiciled in this country: They reside here, with ‘an intention to remain,’” the challengers add.

From The Wall Street Journal • Mar. 31, 2026

The sweeps split families, cost businesses millions of dollars and drove many undocumented residents into hiding.

From Los Angeles Times • Mar. 26, 2026

For decades, the government managed a fragile truce with undocumented immigrants, who in return for paying taxes using an Individual Taxpayer Identification Number, would not have their financial disclosures given to immigration enforcement agencies.

From Salon • Mar. 12, 2026

It had been only a year since I'd discovered we were undocumented, so I didn't quite grasp the gravity of the day our Social Security cards finally arrived in the mail.

From "Americanized" by Sara Saedi