The term masterpiece is one which has gained
many connotations through overuse in contemporary
society.
Originally (and still in certain circles) the
word was used to describe the work created by an
apprentice to demonstrate the skills and knowledge
learned. Every last bit of the apprentice's energy and
patience would be put into this work, making it the best
one (so far) of his (not often her) career. After
completing a masterpiece, the apprentice would be able to
market his (or her) own skills and begin training
apprentices as a recognized master. It was the way of
things among those who worked any trade -- from art to
metalwork to carpentry. Think of the master's thesis
one produces during graduate school: After completing
this daunting task, one has survived a "trial by fire"
and generally receives certification (in the form of
a degree) stating that one is qualified to not only
practice in their field but teach in it as well.
Michaelangelo's Pieta is one of the best-known
masterpieces. He was so proud of this work that he
vowed never to finish another, so as to prevent later
pieces from possibly being interpreted as "better"!
Of course, nowadays (and apparently even in Webster's
1913 days, below) the term applies to virtually any
critically-acclaimed work of art and is even used to
describe works which would theoretically be well before
or after the creator's passage from learner to teacher
(assuming the transition is made at all). Check any
newspaper's movie reviews for a good example.
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