General Antonyms:
* Novice: Someone who is new to a particular activity or skill.
* Beginner: Similar to "novice," but can also be used for someone starting a new job or role.
* Amateur: Someone who does something for pleasure or without professional training.
* Ignorant: Lacking knowledge or understanding of something.
* Uninformed: Not having knowledge about a particular subject.
Specific Antonyms:
* Inept: Lacking skill or competence in a particular area.
* Unqualified: Not having the necessary skills or experience for a task.
* Unskilled: Lacking the necessary skills for a task.
* Rookie: A person who is new to a job or activity.
The best antonym will depend on the specific context in which you are using the word "maven."