postern
Situated at the rear; posterior.
obsolete
[H]e [Arius] fell head-long, and burſting aſunder in the midſt, immediately expired. Socrates and others ſay, that the Bovvels, and all the Inteſtina, vvith a vaſt Flux of blood iſſued out at the Poſtern paſſage.
Lower in quality or status; inferior, lesser.
obsolete
[T]heir Aſſembly (as Philoſophers think the VVorld) conſiſts of Atoms; petty ſmall Levites, vvhoſe Parts are not perceptible. And yet theſe inferiour poſtern Teachers have intoxicated England, (for a man ſometimes grovv's drunk by a Gliſter.)
Clandestine, hidden, secret; also, dishonourable, underhand.
obsolete
Sooner the in-ſide of thy hand ſhall grovv / Hiſped [hispid], and hairie, ere thy Palm ſhall knovv / A Poſtern-bribe tooke, or a Forked-Fee / To fetter Juſtice, vvhen She might be free.
Where it comes from
The noun is derived from Middle English postern, posterne (“side door or gate; small entranceway; hidden or secret door or passage”), from Late Latin posterna, and from its likely etymon Anglo-Norman posterne and Old French posterne (“hidden exit from a fortified building; back door; small door”) (modern French poterne), a variant of posterle (“back door or passage”) (although this is attested later), possibly also influenced by Latin externus (“external, outward”) and internus (“internal, inward”). Posterle is from Late Latin posterla, posterula (“(small) back door, gate, or way”), from Latin posterus (“coming after, later, next”) (from post (“after; behind”), ultimately from Proto-Indo-European *pós (“afterwards; at, by”)) + -ula (suffix denoting an instrument). The adjective is from an attributive use of the noun.
Adapted from the Wiktionary entry postern (CC BY-SA 4.0).