buff
UK[bʌf]US[bʌf]
n
Definition 1: a person who is very interested in and knows a lot about a particular subject
n
Definition 2: a pale yellow-beige colour
v
Definition 3: to polish something, especially metal, to make it shine
adj
Definition 4: of a pale yellow-beige colour
Etymology
The word 'buff' began its journey in English referring to a type of leather made from buffalo hide, which had a characteristic pale, yellowish-brown colour. This leather was notably used in the 16th and 17th centuries to make military coats for firefighters in New York City, who were thus called "buffs." Their enthusiastic, volunteer-like association with firefighting led to the term being applied to any person with a keen, amateur enthusiasm for a specific subject. Concurrently, the colour of the leather gave its name to the shade "buff," and the action of polishing leather to a high shine gave us the verb "to buff."
Analysis
The word 'buff' is a simplex word. It originated as a loanword from the French 'buffle' (meaning "buffalo"), which itself came from the Italian 'bufalo', tracing back to the Late Latin 'būfalus' and ultimately the Greek 'boúbalos' (a kind of antelope or wild ox).
Examples
He's a real film buff and can name every Oscar winner.
The walls were painted in a soft buff.
He buffed the car's paintwork until it gleamed.