the movie title "Babel" is inspired by the story of the Tower of
Babel.
It was a tower built by a united humanity to reach the heavens.
God, observing the unity of humanity in the construction, resolves
to destroy the tower and confuse the previously uniform language of
humanity. without a uniform language, humanity is unable to
communicate with one another and therefore cannot build the
tower.
this pretty much relates to the movie, which centres around
miscommunication with one another.
btw, Babel is composed of two words, "baa" meaning "gate" and "el,"
"god." Hence, "the gate of god."