“The doctor will be with you in just a moment.”
You're at a doctor's office to get checked up for a pain in your knee. Your nurse says this after she's taken you to the examining room.
The doctor will be with you in just a moment.
This is a polite formal phrase often used with customers, guests, or patients to ask them to wait. Several different words can be used to mean "soon" in this phrase:
He'll be with you shortly.
I'll be with you soon.
He'll be with you in just a second.
She'll be with you in just a minute.
This is a polite expression to mean "soon". "Just a moment" is more polite and formal than other choices like "just a second", which sounds more casual.
"In just a moment" also sounds friendlier and sounds like a shorter time than "shortly" or "momentarily".