adeptness adeptness /əˈdɛptnɪs/

noun

1. Skillful performance or ability without difficulty  ( adeptness , deftness , facility , adroitness , quickness )
   skillful performance or ability without difficulty
    His quick adeptness was a product of good design
   his quick adeptness was a product of good design
    He was famous for his facility as an archer
   he was famous for his facility as an archer