banneret (n.)

c. 1200, "piece of cloth attached to the upper end of a pole or staff," from Old French baniere "flag, banner, standard" (12c., Modern French bannière), from Late Latin bandum "standard," borrowed from Frankish or another West Germanic source, from Proto-Germanic *bandwa- "identifying sign, banner, standard," also "company under a banner" (source also of Gothic bandwa "a sign"), from suffixed form of PIE root *bha- (1) "to shine."

Formerly the standard of a king, lord, or knight, behind which his followers marched to war and to which they rallied in battle. The figurative sense of "anything displayed as a profession of principles" is from early 14c. Of newspaper headlines that stream across the top of the page, from 1913.

*bhā-, Proto-Indo-European root meaning "to shine."

It forms all or part of: aphotic; bandolier; banner; banneret; beacon; beckon; buoy; diaphanous; emphasis; epiphany; fantasia; fantasy; hierophant; pant (v.); -phane; phanero-; phantasm; phantasmagoria; phantom; phase; phene; phenetic; pheno-; phenology; phenomenon; phenyl; photic; photo-; photocopy; photogenic; photograph; photon; photosynthesis; phosphorus; phaeton; sycophant; theophany; tiffany; tryptophan.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit bhati "shines, glitters;" Greek phainein "bring to light, make appear," phantazein "make visible, display;" Old Irish ban "white, light, ray of light."