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ad arbitrium

American  
[ahd ahr-bi-tree-oom, ad ahr-bi-tree-uhm] / ɑd ɑrˈbɪ triˌʊm, æd ɑrˈbɪ tri əm /

adverb

Latin.
  1. at pleasure; at will.


Etymology

Origin of ad arbitrium

Literally, “at (one's) control or decision”