Name ambush describes the situation when an acquaintance you haven't seen for a long time comes across and greets you by name but you cannot remember their name at that moment. You know this is embarrassing, but you can do nothing about it.
Name ambush指你偶然遇到一位很久沒見、本來也不太熟的朋友,，對方叫著你的名字跟你打招呼,，可是你一時間卻想不起對方的名字。我們可以戲虐地稱之為“姓名伏擊”,。你知道這樣挺尷尬的,，可是你也沒辦法。
For example:
Joe: "Hi, Andy. How have you been?"
Joe: 安迪,，你好,，最近怎么樣？
Andy: "Er...Hi. Good. How about YOU?"
Andy: 呃,，還行,。你呢？
Sarah: "Andy, you've just been name ambushed."
Sarah: 安迪,，你剛才沒想起他的名字吧,。（中國日報網(wǎng)）