costrel
noun
cos·trel ˈkä-strəl 
: a flat usually earthenware container for liquids with loops through which a belt or cord may be passed for easy carrying
called also pilgrim bottle
Word History
Etymology
Middle English, from Medieval Latin & Anglo-French; Medieval Latin costrellus, from Anglo-French *costrel, from costere side, from coste rib, side — more at coast
First Known Use
14th century, in the meaning defined above