middle name
noun [ C ] uk/ˌmɪd.əl ˈneɪm/ us/ˌmɪd.əl ˈneɪm/
中名（名和姓之间的名字）
the name some people have between their first name and their last name
Idiom
be someone's middle nameidiom informal 是（某人的）突出个性
to be a quality that is an important part of someone's character
Don't worry, I won't tell anyone. Discretion is my middle name. 别担心，我不会告诉别人的。谨慎是我的一大特点。