I have often remarked on the debt that the Anglo-American legal lexicon owes to French and Latin.  Greek has made a much smaller contribution.  In reading Professor Peter Heather's The Fall of the Roman Empire: A New History of Rome and the Barbarians (Oxford University Press), I came across a legal term of obviously Greek origin that I had not yet the pleasure of meeting - "emphyteutic lease".  It turns out that an emphyteusis is a form of tenure developed by the Romans.  An emphyteutic lease allowed a tenant (aka emphyteuta) to occupy and use land indefinitely provided the tenant made some improvements and paid rent.  After the final defeat of Carthage, the Roman State acquired vast tracts of undeveloped land in North Africa.  The Romans effectively used emphyteusis to develop its state owned lands into the breadbasket of the Empire.

Emphyteusis did not disappear with the fall of the Rome.  I was able to find a handful of references to it in U.S. court cases including a couple of U.S. Supreme Court cases, both of which quote the laws of "Porto Rico".  Romeu v. Todd, 206 U.S. 358 (1907) and Sixto v. Sarria, 196 U.S. 175 (1905).  Alas, the word has yet to find itself into the lexicon of the California courts.

The term "emphyteusis" is a transliteration of the Greek word ἐμφύτευσις.