What does it mean to "design" an app?

We use the word "design" for lots of different things and in lots of different ways. 

Not all meanings are the same. I think we'd benefit from clarifying what we mean when we say the word, or we could use different (or additional) words.

The dictionary has lots of meanings for "design".
I like the broad definition of "to intentionally create something to meet pre-defined requirements."

I think of design as more than how something looks; it also includes how it works, behaves, and is used.

A "good" designer can create something that looks nice.

A "great" designer can create something effective, effortless, pleasurable, and desirable to use.
This typically involves more than just how it looks and is intrinsic to a thing, not something that's added at the end.

When "designing an app", what are the different people involved doing?

During the "design phase," what are different people doing?

If doing anything relating to the UI, does that count as "design"?

Is design something that's done to a piece of software once it technically works so that it looks nicer?

When is "design time" from a coder's perspective? Is it all the time up until they start running (or debugging) the code?

Is design something we work as a team to do, to produce the [best] final product?

Is design only about colors and shapes? Or does it require a lot more thought and iteration to do well?

When we talk about "designers" referring to people and roles, we frequently add extra words to make it clear what type of designer we mean, or the type of designing they're doing.

When we talk about "designers" referring to tools, there often isn't the effort to clarify. Should there be? Is what you mean by a designer the same as what I mean by a designer? Depending on context or circumstance, probably not.

What do we mean by "design", and what do we expect from a "designer"?
 - I'm sure I'll keep coming back to these questions.