Consummate
late Middle English (as an adjective in the sense ‘completed, accomplished’): from Latin consummat- ‘brought to completion’, from the verb consummare, from con- ‘altogether’ + summa ‘sum total’, feminine of summus ‘highest, supreme’.
wiktionary
From Latin cōnsummātus, past participle of cōnsummāre(“to sum up, finish, complete”), from com-(“together”) + summa(“the sum”) (see sum, summation).
etymonline
consummate (adj.)
c. 1500, "complete, perfect, carried to the utmost extent or degree," from Latin consummatus "perfected, complete," past participle of consummare "sum up, complete," from assimilated form of com "together, with" (see con-) + summa "sum, total," from summus "highest" (see sum (n.)). Of persons, "accomplished, very qualified," from 1640s. Related: Consummately.
consummate (v.)
mid-15c., "to bring to completion, finish by completing what was intended," from Latin consummatus, past participle of consummare "to sum up, make up, complete, finish," from assimilated form of com "together, with" (see con-) + summa "sum, total," from summus "highest" (see sum (n.)).
Meaning "to bring a marriage to completion" (by sexual intercourse) is from 1530s. Related: Consummated; consummating.
