OPTIONALLY Antonyms

• basic and fundamental

• being or relating to or containing the essence of a plant etc

• defining rights and duties as opposed to giving the rules by which rights and duties are established

• anything indispensable

• absolutely necessary; vitally necessary

• of the greatest importance

• produced by or subjected to forcing

• forced or compelled

• made necessary by an unexpected situation or emergency

• lacking spontaneity; not natural

• requiring attention or action

• relating to verbs in the imperative mood

• a mood that expresses an intention to influence the listener's behavior

• some duty that is essential and urgent

• a verb in the imperative mood.

• the recipient of a mandate

• a territory surrendered by Turkey or Germany after World War I and put under the tutelage of some other European power until they are able to stand by themselves

• required by rule

• absolutely essential

• anything indispensable

• unavoidably determined by prior circumstances

• morally or legally constraining or binding

• required by obligation or compulsion or convention

• necessary for relief or supply

• required by rule

• impossible to avoid or evade

• Something that is not negotiable.

• Not negotiable; not subject to negotiation.

• in an obligatory manner

• in a manner that cannot be evaded