Wikipedia
"Vexilloid" is a term used tenuously to describe vexillary (flag-like) objects used by countries, organizations, or individuals as a form of representation other than flags. Whitney Smith coined the term in 1958, defining it as:
"Vexilloid" can be used in a broader sense of any banner (vexillary object) which is not a flag (that is, taking only Smith's first sentence into account). Thus it includes vexilla, banderoles, pennons, streamers, standards, and gonfalons.
The first most primitive proto-vexilloids may have been simply pieces of cloth dipped in the blood of a defeated enemy in pre-historic times, and the precursors of all later vexilloids and flags.
The use of flags replaced the use of vexilloids for general purposes during late medieval times between about 1100 to about 1400 . However, vexilloids still remain in use for specialized purposes, such as for some military units or to symbolize various organizations such as fraternal organization in street parades.