noun
                                                anything indispensable
                                                                                                Synonyms
                                                
                                                
                                                                                                Examples
                                                
                                                                                                        - 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
 
                                                                                        
                                                adjective
                                                absolutely necessary
                                                                                                Synonyms
                                                
                                                
                                                                                                Examples
                                                
                                                                                                        - vitally necessary
- essential tools and materials
- funds essential to the completion of the project
- an indispensable worker
 
                                                                                        
                                                adjective
                                                basic and fundamental
                                                
                                                                                                Examples
                                                
                                                                                                        - the essential feature
 
                                                                                        
                                                adjective
                                                of the greatest importance
                                                                                                Synonyms
                                                
                                                                                                                                                                        all-important(a)
                                                                                                                                                                                                                                all important(p)
                                                                                                                                                                                                                                crucial
                                                                                                                                                                                                                                of the essence(p)
                                                                                                                                                             
                                                
                                                                                                Examples
                                                
                                                                                                        - the all-important subject of disarmament
- crucial information
- in chess cool nerves are of the essence
 
                                                                                        
                                                adjective
                                                being or relating to or containing the essence of a plant etc
                                                
                                                                                                Examples
                                                
                                                                                                        - essential oil
 
                                                                                        
                                                adjective
                                                defining rights and duties as opposed to giving the rules by which rights and duties are established
                                                                                                Synonyms
                                                
                                                
                                                                                                Examples
                                                
                                                                                                        - substantive law