What does "coolth" mean?

The state of being cool, temperature-wise; coolness.

What is a synonym for "coolth"?

Common synonyms include: absolute zero, balance, bitterness, chill, coldness, cool.

/kuːlθ/ noun

noun ·Rare ·Advanced level

Noun

1
The state of being cool, temperature-wise; coolness. uncountable, usually
"Froid: m. Cold, cooth^([sic]); coldneſſe, chilneſſe."

"Froid: m. Cold, cooth^([sic]); coldneſſe, chilneſſe."

From cool + -th (abstract nominal suffix). Compare Old Dutch kuolitha (“coolness”).