1. A drama or literary work in which the main character is brought to ruin or suffers extreme sorrow, especially as a consequence of a tragic flaw, moral weakness, or inability to cope with unfavorable circumstances; the genre made up of such works and the art or theory of writing or producing these works: William Shakespeare is noted for his many dramas called tragedies, like Hamlet, Prince of Denmark.

A tragedy can also be a play, film, television program, or other narrative work that portrays or depicts calamitous events and has an unhappy but meaningful ending.
3. A disastrous event, especially one involving distressing loss or injury to life: It was an expedition that ended in tragedy, with all hands lost at sea.
4. A tragic aspect or element, such as a lamentable, dreadful, or fatal event or affair; a calamity; a disaster: The people of many countries are experiencing the tragedies of war every time the news tells of more deaths.
5. Etymology: from Old French tragedie (14th century); from Latin tragedia, "a tragedy"; from Greek tragodia, "a dramatic poem or play in formal language and having an unhappy resolution"; apparently literally, "goat song", from tragos, "goat" + oide, "song".

More etymological information about tragedy.