What does "sponsion" mean?

The act of becoming surety for another.

What is a synonym for "sponsion"?

Common synonyms include: sponsorship.

noun

noun ·Rare ·Advanced level

Noun

1
The act of becoming surety for another. countable, uncountable
2
An act or engagement on behalf of a state, by an agent not specially authorized for the purpose, or by one who exceeds the limits of authority. countable, uncountable

From Latin spōnsiō, from spondēre (“to promise solemnly”).