That is the friendly greeting that means both "hello" and "goodbye" in the native Hawaiian language.

VOA: special.2009.08.02

If it's a true happiness smile, that's actually bodes better for the relationship than a Pan Am, or greeting smile.

如果是一个真正开心的微笑，对这段感情来说是个好兆头,比问候式微笑好的多。

耶鲁公开课 - 心理学导论课程节选

As I'm out here meeting and greeting the tourists,

我在这里见游客、打招呼，

我就是超人 - SpeakingMax英语口语达人

The State Department said Monday the administration still has a hand extended to Iran despite the chilly reaction by Iran's supreme leader to Mr.Obama's videotaped holiday greeting to Iran late last week, in which he said the United States seeks honest engagement with Iran's Islamic government based on mutual respect.

VOA: standard.2009.03.23

such as a distinction between the Pan Am smile, a greeting smile, versus a genuine smile of happiness?

像泛美式微笑，问候式微笑，同真心微笑的区别？

耶鲁公开课 - 心理学导论课程节选

The one on the right is a smile of greeting.

右边是打招呼的微笑。

耶鲁公开课 - 心理学导论课程节选

So, you have two sorts of smiles: A real happiness smile a Duchenne smile--called--also known as the Duchenne smile, and then a Pan Am smile, or greeting smile.

所以，有两种微笑：,真正开心的微笑,杜乡式微笑，泛美式微笑，或问候式微笑。

耶鲁公开课 - 心理学导论课程节选