The French word used in Ballet
to decribe a bend of the leg
at the knee
while keeping the back
straight. It is derived from the past participle
of the word "plier" meaning "to fold
It is pronounced as "plee-ay," with the emphasis on the first syllable, and is generally considerd the most common step in Classical and Romantic Ballet. This has given rise to the frequent lament among dancers, "Another day, another plie." (Note that in this phrase "day" and "plie" rhyme, hence the humor).
And in case you were wondering, all ballet steps are named in French.