proficiency
//prəˈfɪʃənsi//
Noun
proficiencySingular
proficienciesPlural
1
A high degree of skill or competence in a particular area, acquired through training or practice.
She demonstrated her proficiency in Japanese after years of study.
2
The state or quality of being proficient; expertise or mastery in a subject or activity.
Her proficiency in Japanese impressed everyone at the meeting.