first-timer
构词拆分
first time词根/词干
+
-er后缀
(added to verbs) A person or thing that does an action indicated by the root verb; used to form an agent noun. · (added to verbs, informal) A person or thing to which the root verb is done or can be done satisfactorily.
词源说明
释义（英文）
名词 Noun
- a person engaging in any activity for the first time