A man purse or murse. Also, comenly reffered to as a sathcel. Different from a back pack or book bag in that it usually only has one strap. Can be carried over the shoulder or cross body, like a messanger bag (even worse than over the shoulder, if you can imagine). In a few rare instances, the strap may only allow it to be carried using just one hand, like a PURSE. Unless you are actually from Europe & still in Europe (and even then I would question it), the "ESB" is completely unacceptable. Usually, carrying one will undoubtedly have you mistaken as being gay.
Progressive commercial where the man is accused carrying the ladies purse, NOPE it's actually a european soldier bag bought by the wife.

The Hangover, "It's not a man purse, it's called a satchel, Idiana Jones wears one." NO DUDE, it's a ESB. thanks.
by Textmessagebreakup August 4, 2011
Get the european soldier bag mug.