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ab initio

play
adverb ab in·i·tio \ˌab-ə-ˈni-shē-ˌō\

Definition of ab initio

  1. :  from the beginning



Did You Know?

We’ll tell you right from the beginning where "ab initio" comes from. This adverb was adopted at the end of the 16th century directly from Latin, and it translates, unsurprisingly, as "from the beginning." ("Initio" is a form of the noun initium, meaning "beginning," which gave rise to such English words as "initial," "initiate," and "initiative.") "Ab initio" most frequently appears in legal contexts, but our example sentence is not out of the norm. Recently, people have also begun using "ab initio" as an adjective meaning "starting from or based on first principles" (as in "predicted from ab initio calculations").

Origin of ab initio

Latin


First Known Use: 1599


Law Dictionary

ab initio

play
adverb ab ini·tio \ˌab-ə-ˈni-shē-ˌō, ˌäb-i-ˈnē-tē-ˌō\

Legal Definition of ab initio

  1. :  from the beginning <a contract found to be void ab initio>



Origin of ab initio

Latin


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