Vexillology

Vexillology is the scholarly study of flags. The word is a synthesis of the Latin word vexillum, meaning 'flag', and the Greek suffix -logy, meaning 'study'. The vexillum was a particular type of flag used by Roman legions during the classical era; its name is a diminutive form of the word velum meaning 'sail', and thus literally means 'little sail'. Unlike most modern flags, which are suspended from a pole or mast along a vertical side, the square vexillum was suspended from a horizontal crossbar along its top side, which was attached to a spear.