What does "final say" mean?

The right to make a final decision.

What is a synonym for "final say"?

Common synonyms include: absolute authority, exclusive jurisdiction.

noun

noun ·Rare ·Advanced level

Noun

1
The right to make a final decision. idiomatic
"In all matters relating to the family business, mum has the final say."

"In all matters relating to the family business, mum has the final say."