what's the difference between words 'Procurement' and 'Purchasing'

None :D

Procurement and purchasing are two terminologies often used to describe the same function, but these two have subtle differences. Procurement is the act of getting or providing so this includes the activities related to purchasing goods, services, and work for a company. It includes all the phases and aspects of purchase, from beginning to the end process. On the other hand, purchasing is the act of buying.Purchasing involves payment to the acquired products, services, etc. Procurement also involves the acquisition of something through other process but not necessarily and not always by purchase.

None as far as I can see. Workmates can be tw-ats

In simple terms, it's "get" and "buy"! Procurement doesn't necessarily mean you are buying something. You could be using a barter system, or borrowing something, or just moving things that you already own to where they are needed. Purchasing obviously means that payment must be made, but it could be up-front, on delivery, or on credit. Of course, in some cases, they mean the same!