What does "beating heart" mean?

The core of a thing; its most essential or important part.

What is a synonym for "beating heart"?

Common synonyms include: anima, atman, biological clock, biorhythm, blood, breath.

noun

noun ·Rare ·Advanced level

Noun

1
The core of a thing; its most essential or important part. figuratively
"the beating heart of the economy"
2
Used other than figuratively or idiomatically: see beating, heart.
"beating-heart transplant"

"the beating heart of the economy"