This word Fesse is a French word, and doth signifie the Loines of a man. This Ordinary hath beene anciently taken for the same that wee call Baltheum militare, or Cingulum honoris, a Belt of honours: because it divideth the Field into two equall parts, it self occupying the middle between both; even as the Girdle environeth the middle part of a man, and resteth upon his Loines.
Hitherto of a Barre: Now of a Gyronne: A Gyronne is an Ordinarie consisting of two straight lines drawen from divers parts of the Escocheon, and meeting in an Acute-Angle in the Fesse Point of the same. A Gyronne (as one saith) is the same that we call in Latine Gremium, which signifieth a Lappe, and is the space betweene the thighes: and thence perchance doe we call the Groyne; which name, whether it be given to this charge because it determines in gremio, in the very lappe or midst of the Escocheon, or because it hath a bending like the thigh and legge together, I cannot define. Gyrons are borne diversly, viz. single, by couples, of six, of eight, of ten, and of twelve, as shall appeare heereafter, where I shall speake of Armes having no tincture predominating. For the making this Ordinarie, behold this next Escocheon, where you shall finde one single Gyronne alone, which doth best expresse the maner thereof, as in example.
This word Flanch (as some doe hold) is derived from the French word Flans, which signifieth the Flanke of man or beast, that includeth the small guttes, because that part strouteth out, cum tumore quodam, as if it were a blowne bladder. Sometimes you may finde this Ordinary made of some other forme of Lines then plaine, which when it shall happen, you must in the blazon thereof, make speciall mention of the forme of Line whereof it is composed.
via A DISPLAY OF HERALDRIE: by John Guillim