cognominal

Of or relating to a cognomen.

[T]he cognomen, indicator par excellence of the stable, geographically localized, diachronically perpetuated lineage, is an emblem of patrilineal prestige. The poem's invidious perception of the cognomen is reflected in the frequent repetition of the toponym associated with the Cid's foes: "Carrión." Used 135 times (versus 22 examples for Vivar), the name occurs in most instances as a component of the cognominal formula "iffantes de Carrión" [...] with the cognomen "de Carrión" appearing far more frequently than the patronym González[…]

A name (sometimes especially one's cognomen or family name).

[…] Mr. Diedrich Knickerbocker, a name not yet ranked with Hume, and Gibbon, and Robertson, very fortunately for those who have an antipathy to Dutch cognominals, but which, we venture to foretel, will be held in esteem,

On reference to Clarkson's History of Richmond, compiled chiefly from Gale's Register Honorum Richmondæ, it appears that a charter of Alan, fourth Earl of Richmond, is witnessed in 1145, among others, by THEOBALD and by BALDWIN, and another similar charter in the subsequent year by Baldwin de Multon (Malton), in Richmondshire, the patrimony of the Earls of Richmond. Baldwin would thus appear to have been connected with the Earls of Richmond, as holding lands under them, prior to the appearance of the name in connexion with Scottish record; and, although the occurrence of even one of those uncommon names, THEOBALD or BALDWIN, on record in England, at a period so immediately preceding its first appearance in Scotland, would lead to infer the probable identity of the individual bearing the appellation, that identity may surely be assumed as resting upon sufficient grounds when two individuals of such remarkable cognominals (from the same country) can thus be traced in mutual transactions in both kingdoms. And if the connexion thus apparent between Baldwin and the Earl of Richmond can be shown to have extended itself more intimately on the part of Baldwin with the family of Crawfurd, which, in ignorance of the present adduced facts, we have already traced on entirely distinct grounds to those earls as its source, […]

Bearing the same name.

... is the pole cognominal with the pole of the magnet; and inasmuch as the cognominal poles of magnets repel each other, so are we to conceive this one also as repelled by the pole of the magnet.

Divide any arc of revolution into 90 equal parts from the terminus of the arcs of revolution to the pole; for whatever the degree of latitude of the place, that part of the arc of revolution is to be reckoned as cognominal to it which the magnetic pole in rotating upon or around terrella or earth regards: in the large diagram that follows, this is indicated by the right lines.