Ipso facto is Latin and is defined as by the fact.(adverb)
If all squares are rectangles and all rectangles have four sides, this is an example of when a square has four sides ipso facto.
See ipso facto in Webster's New World College Dictionary
See ipso facto in American Heritage Dictionary 4
Origin: New Latin ipsō factō
Origin: : Latin ipsō
Origin: , ablative of ipse, itself
Origin: + Latin factō
Origin: , ablative of factum, fact.
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