Need some help with Mechanical Engineering and Machining terms

Hi guys, I am a student of the Electrical and Computer department of University of Toronto and I am going through a thesis titled A power assessment of Machining tools by David Kordonowy.

I am new to mechanical engineering and there are a few terms and concepts related to machining (especially CNC machining) that is not at all familiar with, I hope you can help me with some of these.

I already know the general terms such as milling, turning (lathe), material removal rate... which at first I was not very clear on, here are the terms that I need help with:

1. The author used the word "cut" very generally. Is drilling considered "cutting"?

2. What does the terms "loaded" and "unloaded" mean? For example I don't really understand the phase "unloaded hydraulic motor". Does it mean that it is in operation?

3. When does "feeding" occur? And why its unit is defined as (inch/rev) if feed means that the component moves the workpiece linearly?

4. How does the "phase" of a motor defines the property of a motor? What is a 3 phase or single phased motor?

Lastly, there is an odd term called "flute" that is sometimes used in conjunction with "width" therefore becoming flute width. I am not at all clear as to what this maybe I don't know if you could help out.

Thank you in advance!

First of all let me welcome you to CE Hybodus. 😀
The following are my answers
1. 'Cut' is a general word in manufacturing. Cutting means material removal. So in the context of your question, drilling may be called cutting. You are right on that count.
2. Unloaded means the machine is disengaged . An unloaded hydraulic motor means that the motor is not in operation (i.e.; it is disengaged). It is lying idle.
3. During feeding, the tool or the work-piece is rotated about an axis.
In case of a lathe machine, the tool advances. (Considering the cross section of the work piece is constant throughout its length) the material removed for every rotation is called feed.
For example in one revolution, the material removed is 1 inch. Means the total material removed is (1 inch* CS are/revolution)
4. In a 3-phase motor, three conductors are carrying three different ac currents. These currents are of same frequency. But the timing of their reaching peak voltage is different.
The single phase has a single conductor.
5. For flute width see this diagram #-Link-Snipped-#