This term refers to business terminology where one word replaces the use of many. We often use abbreviations here. The old-style business letter was full of jargon, which came to be called commercialise. We should fight against this artificial way of writing at all costs.
Examples of commercialisation: "C.O.D." (cash on delivery), "Paid on account".
Avoid exaggerations e.g. "a thousand apologies", in business writing. Say only what you think is necessary. Avoid words like "gigantic" and "immeasurable", if what you really mean is "large" or "considerable".