Definitions

1. noun

the essential or most important part of something; the source of its vitality or strength

“The university’s research department is the lifeblood of its academic programs.”

2. noun

a person or thing that is essential for the functioning or success of something

“The star player was the lifeblood of the team’s chances of winning the championship.”

3. noun

the central or most vital part of an organization or system

“The IT department is the lifeblood of the company, keeping all systems running smoothly.”