Indispensable (9)
'indispensable' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for essential that I've seen before include "something necessary" , "Key" , "organic" , "So is certain oil-production" , "Type of oil" .)
'indispensable' is the definition.
(associated in meaning)
This is all the clue.
(Other definitions for necessary that I've seen before include "the money?" , "Essential or unavoidable" , "Inescapable" , "Indispensable, essential" , "Requisite" .)
'indispensable' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for basic that I've seen before include "Fundamental -- early computer language" , "Key" , "No-frills" , "vital" , "At the simplest level" .)
'indispensable' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for vital that I've seen before include "Essential, life-giving" , "Necessary for life" , "Urgently needed or absolutely necessary" , "Essential to life, indispensable" , "Desperately important" .)
(Other definitions for invaluable that I've seen before include "Extremely useful" , "Priceless" .)