con·sum·mate • v. / ˈkänsəˌmāt/ [tr.] make (a marriage or relationship) complete by having sexual intercourse. ∎  complete (a transaction or attempt); make perfect.• adj. / ˈkänsəmət; kənˈsəmət/ showing a high degree of skill and flair; complete or perfect: she dressed with consummate elegance.DERIVATIVES: con·sum·mate·ly / ˈkänsəmətlē; kənˈsəmətlē/ adv.con·sum·ma·tor / ˈkänsəˌmātər/ n.

consummate pp. †completed XV; adj. complete, perfect XV. — L. consummātus.
So consummate vb. bring to completion. XVI. f. L. consummāre, -āt-, f. CON- + summa SUM, summus highest, utmost, supreme; see -ATE 2, -ATE 3. consummation completion, perfection XIV; crowning end XVII. — (O)F. consommation or L. consummātiō.

CONSUMMATE

To carry into completion; to fulfill; to accomplish.

A common-law marriage is consummated when the parties live in a manner intended to bring about public recognition of their relationship as husband and wife.

To consummate an agreement is to carry it out completely, as in a consummated sale. It is to bring to completion whatever was either intended or undertaken to be done.