D defs.my
Entry 3 senses Webster, 1913

Indispensable

/ĭnˌ-dĭs-pĕn'-səb-əl/ · In·dis·pen·sa·ble · IPA /ˌɪndɪˈspɛnsəbəl/
01 a. Not dispensable; impossible to be omitted, remitted, or spared; absolutely necessary or requisite.
  1. 1.
    Not dispensable; impossible to be omitted, remitted, or spared; absolutely necessary or requisite.
  2. 2.
    Not admitting dispensation; not subject to release or exemption.(Eccl.) [R.]
    “The law was moral and indispensable.” Bp. Burnet.
  3. 3.
    Unavoidable; inevitable.[Obs.]