What is the term for someone who is new to a field or activity?

The term "tyro" refers to someone who is a beginner or novice in a particular field or activity. This word is derived from the Italian "tirocinio," which means an apprentice or trainee. The essence of being a tyro is characterized by a lack of experience and a willingness to learn, making it an ideal term to describe individuals who are just starting out in a new venture.

In contrast, the other choices do not convey this meaning. "Supercilious" describes someone who is haughty or snobbishly patronizing, which is entirely unrelated to being a beginner. "Succor" refers to assistance or support in times of difficulty, and while it can relate to those in need of help, it doesn’t pertain to one’s experience level. "Venal" pertains to corruptibility or willingness to be bribed, again unrelated to the concept of being a newcomer. Thus, "tyro" stands out as the specific term that denotes someone new to a field or activity.