n (context|medicine|obsolete) A sedimentarydeposit, especially in urine. (defdate|14th-19th c.)
n (theology) The essential person, specifically the single person of Christ (as distinguished from his two ‘natures’, human and divine), or of the three ‘persons’ of the Trinity (comprising a single ‘essence’). (defdate|from 16th c.)
n (philosophy) The underlying reality or substance of something. (defdate|from 17th c.)
n (genetics) The effect of one gene preventing another from expressing. (defdate|from 20th c.)