A bag or case with one or two shoulder straps, especially used to carry books etc.
(US slang) a man's purse
A little sack or bag for carrying papers, books, or small articles of wearing apparel; a hand bag.
‘The whining schoolboy with his satchel.’;
(US slang) a male nurse
luggage consisting of a small case with a flat bottom and (usually) a shoulder strap
A satchel is a bag with a strap, traditionally used for carrying books. The strap is often worn so that it diagonally crosses the body, with the bag hanging on the opposite hip, rather than hanging directly down from the shoulder.