| essential | anything indispensable |
|---|---|
| essential | (law) applying to essential legal principles and rules of right |
| essential | basic and fundamental |
| essential | absolutely required and not to be used up or sacrificed |
| essential | of the greatest importance |
| essential | absolutely necessary |
| essential | being or relating to or containing the essence of a plant etc |
| essential | an amino acid that is required by animals but that they cannot synthesize |
| essential | a prerequisite |
| essential | persistent and pathological high blood pressure for which no specific cause can be found |
| essential | a volatile oil having the odor or flavor of the plant from which it comes |
| essential | the primary form of thrombocytopenia (rather than a shortage of platelets caused by with other conditions such as tuberculosis or chemical suppression of bone marrow etc.) |