necessary

1. Absolutely essential (synset 301584458)
   also:

   • obligatory - morally or legally constraining or binding
   • essential - basic and fundamental
   • indispensable - not to be dispensed with; essential
   tells us about: necessity - the condition of being essential or indispensable
   similar to:

   • essential, indispensable - absolutely necessary; vitally necessary
   • incumbent - necessary (for someone) as a duty or responsibility; morally binding
   • needed, needful, required, requisite - necessary for relief or supply
   • obligatory - required by obligation or compulsion or convention
2. Unavoidably determined by prior circumstances (synset 300344451)
   "the necessary consequences of one's actions"
   similar to: inevitable - incapable of being avoided or prevented

1. Anything indispensable (synset 109390100)
   "food and shelter are necessities of life"; "the essentials of the good life"; "allow farmers to buy their requirements under favorable conditions"; "a place where the requisites of water fuel and fodder can be obtained"
   is a type of: thing - a separate and self-contained entity
   subtypes:

   • desideratum - something desired as a necessity
   • must - a necessary or essential thing
   • need, want - anything that is necessary but lacking
   same as: essential, necessity, requirement, requisite

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