It refers to the telephone workload consisting of periods of near-non-stop telephone calls for non-receptionist personnel. Individuals are responsible for call details and information forwarding, filing, and follow-up.
how heavy it is most common
"Heavy" is a term used for any aircraft with a certified maximum takeoff weight of over 255000 pounds.
Pesante is Italian for heavy.
Tony Puma. "Experience Makes The Difference".
The term buy phone would seem to suggest that someone is intending to purchase a phone. It does not appear to have any particularly special or different meanings attached to it as a phrase.
I think that a horrow A farm implement consisting of a heavy frame with sharp teeth or upright disks, used to break up and even off plowed ground.
Usually, "lots of people died", e.g. a heavy price in blood. It can also mean "lots of property (things, weapons, materials, buildings, bridges) was destroyed".
Phuket is the Thai word for Thai, and holidays in this sense means "to experience," so the term "phuket holidays" means "to experience Thailand."
A banana dance is a term (slang) meaning crazy dance while a banana phone is a phone shaped like a banana or a slang to mean a crazy phone (with sexual connotations)
"Largo" is a slow, plodding, heavy tempo - like the marching of elephants.
"Gravis" is a Latin word meaning heavy. It can also mean weighty, serious, burdensome, important, severe, grievous, and unwholesome. It can also be written as grauis.
"That is the nature of the business" is a term that means that something happens because it is common experience for the event you are performing or doing. It usually implies a bad experience.