Let me find out <what's up.>

[WilliamTaft]

An example sentence using "up" in The Britannica Dictionary: Your order should have arrived. Let me find out what's up.

Does "what's up" mean "what are they?" or "what is it?"

 

[Tarheel]

Let me find out what's up - Let me find out what's happening OR Let me find out what's going on.

Let's me find out what's up - I'll check to see what's up (what's happening; what's going on).

 

[5jj]

The dictionary says this;

not used before a noun, informal : happening : going on

• I could tell something was up by the look on her face.
• Your order should have arrived. Let me find out what's up.