n.[U][(+of/over)]

1. 支配，統治
   the mastery of the seas

   制海權

2. 優勢，優勝
   The team gained mastery over its opponent.

   該隊勝了對手。

3. 熟練；精通；掌握[S1]
   He has acquired mastery of French.

   他已掌握了法語。

n.

1. comprehensive knowledge or skill in a particular field.
2. the mastering of a subject or skill.
3. control or superiority over someone or something.