What does "unemotionality" mean?

The state or quality of being without emotion.

Unemotionality

Common synonyms include: calmness under pressure, coldness, detachment, emotional restraint, emotionlessness, impassiveness.

noun

noun ·Rare ·Advanced level

Noun

1
The state or quality of being without emotion. uncountable
"His unemotionality was great when he wanted a poker face but prevented him from truly enjoying the happy occasions of life."
2
absence of emotion wordnet
3
apathy demonstrated by an absence of emotional reactions wordnet

"His unemotionality was great when he wanted a poker face but prevented him from truly enjoying the happy occasions of life."

From un- + emotionality.