资料来源 : pyDict

不是必要的,可有可无的

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Dispensable \Dis*pen"sa*ble\, a. [LL. dispensabilis. See
   {Dispense}.]
   1. Capable of being dispensed or administered.

   2. Capable of being dispensed with. --Coleridge.

资料来源 : WordNet®

dispensable
     adj : capable of being dispensed with or done without;
           "dispensable items of personal property" [ant: {indispensable}]