Why is bra singular and panties plural?

Life summarised in 4 bottles http://bit.ly/9kvFgp

The 8 Villains of Social Media http://bit.ly/95dcf3 and your best defense

Flight Attendants Dance to Lady Gaga during safety demos http://bit.ly/9xkAXE The voiceover is a bit unnerving...

University student's sex list becomes internet sensation http://bit.ly/dq8LMN

People still believe The Onion publishes real news?! http://bit.ly/aOUqJD+ Historians Admit To Inventing Ancient Greeks

Why is the word for "a fear of long words," hippopotomonstrosesquippedaliophobia, so long?