D defs.my
Entry 2 senses Webster, 1913

Testament

/tĕs'-təm-ənt/ · Tes·ta·ment · IPA /ˈtɛs.tə.mənt/
01 n. A solemn, authentic instrument in writing, by which a person declares his will as to disposal of his estate and effects after his death.
  1. 1.
    A solemn, authentic instrument in writing, by which a person declares his will as to disposal of his estate and effects after his death.(Law)
  2. 2.
    One of the two distinct revelations of God's purposes toward man; a covenant; also, one of the two general divisions of the canonical books of the sacred Scriptures, in which the covenants are respectively revealed; as, the Old Testament; the New Testament; -- often limited, in colloquial language, to the latter.
    “He is the mediator of the new testament . . . for the redemption of the transgressions that were under the first testament.” — Heb. ix. 15.
Phrases & compounds
Holographic testament — a testament written wholly by the testator himself.