In English-language heraldry, the fillet is considered a diminutive of the chief. It is defined as occupying one fourth the width of the chief and typically positioned at its bottom edge.[1] When so positioned the chief is blazoned as supported by the fillet; but, when the chief is charged by the fillet, as when the fillet positioned at its top edge[2] or middle, the chief is blazoned as surmounted.[3] Another term for the former, supported, is sustained.[4] In French heraldry, terms for this charge are divise[5] and filet en chef.[6] The term chef retrait has also been used.[7] The fillet or divise placed beneath the chief is of a different tincture than the field,[8] evidently to avoid violations of the rule of tincture (see Berry 1828[9]).
There are other uses of the English fillet that are similar to its use above as diminutive of the chief. The term is used by some for a diminutive of the fess narrower than the bar, as a synonym for barrulet.[10] It is also used by some more generally for a narrow band as charge that can be positioned variously on the field—as a diminutive of the bend, as synonym of riband[11] as well as the fess, as synonym of barrulet. This latter use parallels that of the cognate term filet in French heraldry, where it is possible to speak of the filet "en fasce, en pal, en bande, en barre, en croix, en sautoir, en chevron, en parle" (fillet in fess, in pale, in bend, in bend sinister, in cross, in saltire, in chevron, in pall).[12] (See #Fillet as adjective below.)
Such uses of the term fillet in English (or filet in French) often employ it as term for a component element of other devices such as the cross parted and fretted,[13] the ordinary the fret, or the variation of the field fretty.[14] 'Fretted' and 'fretty' refer to the interlacing of the fillets.[15] The Jumelle (Eng. bar gemel, etc.) and Tierce are other charges also said to be composed of filets.[16] The cottise, or cost, has been described as having the "appearance of a fillet placed beside the principal ordinary"[17] and at least one author terms it a fillet.[18] The pentagram has even been described as a "star reduced to an interlaced fillet".[19]
This use of the term, as the diminutive of an ordinary or component of a complex charge, is to be distinguished from other uses of the term fillet in heraldry. See section #Other uses of fillet in a heraldic context below.