Process: Late Middle English, as used in law:

    a.    The whole of the proceedings in any action at law; the course or method of carrying on an action at law.

    b.    The formal commencement of any action at law: the mandate, summons or writ by which a person or thing is brought into court for litigation.

Post:  [Latin postitum; that which is put. 1727]

    1.    To affix (a paper, etc.) to a post or in a public place. To make known, advertise (some fact, thing or person) by or as by posting a placard. 1650. [To expose to ignominy, or ridicule by this means (now obsolete). 1642.]

Poster:

    1.    One who posts or sticks up bills; a bill-poster. 1838.

    2.    A placard placed or displayed in a public place as an announcement or advertisement. 1838.

Summons:

    1.    To cite before a court or a judge or a magistrate. 1658.

    2.    To take out a summons against. 1780.

Summoner:

    1.    A petty officer who cites and warns persons to appear in court. 1580.

    2.    One who takes out a summons. 1865.

Court: Old English [Early Middle English curt, court, a. Old French cort, court, later court. (from 15th century cour) Latin cohortem, cortem. English; first used in 1450, roots in Spanish (cortes) and Middle English.]

Noun: A court of judicature, of law, or of administration.

    1.    Applied to parliament, (Spanish cortes Cf. 1450).

    2.    An assembly of judges or other persons appointed to hear and determine any cause, civil, ecclesiastical, military or naval; Middle English.

    3.    The place, hall or chamber in which justice is administered; Middle English. b. without article (in, into, out of c., etc.) including place and proceedings; Middle English.

    4.    A session of judicial assembly; Middle English.

    5.    An assembly of the qualified members of a company or corporation, or of the council thereof 1527.

Source; Oxford Old English Dictionary