The Negative Prefix il-
From a reader commenting on the illegal alien post:
I used to hear from my history teacher in high school that the word “illegal” isn’t actually a word. I never followed up on that notion, but I suppose from popular usage, “illegal” has become legitimized. Do you have any etymological info on that?
The word illegal with the sense of “not legal or lawful” has been in English since 1626. Similar words existed in Middle English and French as early as the fourteenth century.
The expression illegal immigrant dates from 1939 during the British mandate in Palestine. The term was applied to Jews who entered Palestine without authorization.
The word illegal derives ultimately from Latin: legalis “legal” with the negative prefix in-. The n of the prefix assimilates to l in words that begin with l:
illegal: not legal or lawful
illegible: not legible; incapable of being read
illegitimate: not recognized by law as lawful offspring; not rightly deduced; departing from the expected
illiberal: not liberal; not generous; not broad-minded
illicit: not permitted; not allowed
illimitable: not capable of being limited or bounded
illiterate: unable to read or write
illogical: not logical; contrary to logic