(set phrase) Time is an essential consideration (in regard to an action or response); haste is necessary.
Synonym: no time to lose
When transporting organs for transplant, time is of the essence.
(law, in a contract) Failure to complete the required performance by the date certain set forth will constitute an incurable breach.
Source: en.wiktionary.orgTime is of the essence, and tax abatements and deferments could help right away. Source: Internet
"Time is of the essence to ensure a restart plan can be put in place for next year," a representative of Origin International said, on condition of anonymity, at the time. Source: Internet