A concise way to refer to the process of reducing the length of a word or phrase is "shortening."
Yes brief is an adjective. The word brief can describe something.
Brief means short in length, or in duration. It can also mean to give people short details about a task.
As far as I know the answer is "NO" the definition of brief is...Short in time, duration, length, or extent.Succinct; concise: a brief account of the incident.Curt; abruptUNDER SHORTS
Oxymoron
Allusion:a brief reference to a person, event, place, or phrase
an Epithet
An "overview" is A survey or a broad, comprehensive view of something. A summary or a review of something. And the word "brief" means short. Thus a "brief overview" is a short (in length) summary of something.
buildings.
The phrase "in a nutshell" means to sum something up briefly or concisely. It is often used to provide a brief summary or explanation of a complex topic or situation.
In length, the opposite of long is short. In time, the opposite of long may be short or brief.
The phrase character sketch refers to a brief description of the personality of some person, real of fictional.
Topic outlines are usually brief in length. This type of outline contains keywords and phrases are usually expressed in parallel phrases.