desenvoltura
ease
develop
to grow or progress
+
-ura
noun-forming suffix
Desenvoltura means ease and can be related to the English word develop0 (to grow or progress0) + -ura1 (noun-forming suffix1), suggesting the ease that comes with being well-developed or skilled.
noun
- easeEase and confidence in behavior or mannerHabló con gran desenvoltura frente al público. // He spoke with great ease in front of the audience.