The Collaborative International Dictionary of English v.0.48:

Session \Ses"sion\, n. [L. sessio, fr. sedere, sessum, to sit:
   cf. F. session. See Sit.]
   1. The act of sitting, or the state of being seated.
      [Archaic]
      [1913 Webster]

            So much his ascension into heaven and his session at
            the right hand of God do import.      --Hooker.
      [1913 Webster]

            But Viven, gathering somewhat of his mood, . . .
            Leaped from her session on his lap, and stood.
                                                  --Tennyson.
      [1913 Webster]

   2. The actual sitting of a court, council, legislature, etc.,
      or the actual assembly of the members of such a body, for
      the transaction of business.
      [1913 Webster]

            It's fit this royal session do proceed. --Shak.
      [1913 Webster]

   3. Hence, also, the time, period, or term during which a
      court, council, legislature, etc., meets daily for
      business; or, the space of time between the first meeting
      and the prorogation or adjournment; thus, a session of
      Parliaments is opened with a speech from the throne, and
      closed by prorogation. The session of a judicial court is
      called a term.
      [1913 Webster]

            It was resolved that the convocation should meet at
            the beginning of the next session of Parliament.
                                                  --Macaulay.
      [1913 Webster]

   Note: Sessions, in some of the States, is particularly used
         as a title for a court of justices, held for granting
         licenses to innkeepers, etc., and for laying out
         highways, and the like; it is also the title of several
         courts of criminal jurisdiction in England and the
         United States.
         [1913 Webster]

   Church session, the lowest court in the Presbyterian
      Church, composed of the pastor and a body of elders
      elected by the members of a particular church, and having
      the care of matters pertaining to the religious interests
      of that church, as the admission and dismission of
      members, discipline, etc.

   Court of Session, the supreme civil court of Scotland.

   Quarter sessions. (Eng.Law) See under Quarter.

   Sessions of the peace, sittings held by justices of the
      peace. [Eng.]
      [1913 Webster]

WordNet (r) 3.0 (2006):

session
    n 1: a meeting for execution of a group's functions; "it was the
         opening session of the legislature"
    2: the time during which a school holds classes; "they had to
       shorten the school term" [syn: school term, academic
       term, academic session, session]
    3: a meeting devoted to a particular activity; "a filming
       session"; "a gossip session"
    4: a meeting of spiritualists; "the seance was held in the
       medium's parlor" [syn: seance, sitting, session]

Moby Thesaurus II by Grady Ward, 1.0:

138 Moby Thesaurus words for "session":
   Council of Nicaea, Council of Trent, Lateran Council,
   Vatican Council, abundant year, academic year, annum, assemblee,
   assembly, assignation, at home, audience, ball, bargaining,
   bargaining session, bissextile year, brawl, calendar month,
   calendar year, caucus, century, chapter, classis, colloquium,
   commission, committee, common year, conciliarism, conclave,
   concourse, confab, confabulation, conference, confrontation,
   congregation, congress, consistory, consultation, conventicle,
   convention, convocation, council, council fire, council of war,
   dance, date, day, decade, decennary, decennium, defective year,
   diet, diocesan conference, discussion, ecclesiastical council,
   ecumenical council, eisteddfod, exchange of views,
   eyeball-to-eyeball encounter, festivity, fete, fiscal year,
   forgathering, fortnight, forum, gathering, get-together, hearing,
   high-level talk, hour, housewarming, huddle, interchange of views,
   interview, leap year, levee, lunar month, lunar year, lunation,
   luster, lustrum, man-hour, meet, meeting, microsecond, millennium,
   millisecond, minute, moment, month, moon, negotiations,
   news conference, palaver, panel, parley, parochial church council,
   parochial council, party, period, plenary council, plenum,
   pourparler, powwow, presbytery, press conference, prom, quarter,
   quinquennium, quorum, rally, reception, regular year, rendezvous,
   seance, seating, second, semester, shindig, sidereal year, sit-in,
   sitting, soiree, solar year, summit, summit conference, summitry,
   sun, symposium, synod, term, trimester, turnout, twelvemonth,
   vestry, week, weekday, year



The Free On-line Dictionary of Computing (30 December 2018):

session

    1. A lasting connection between a user (or user
   agent) and a peer, typically a server, usually involving
   the exchange of many packets between the user's computer and
   the server.  A session is typically implemented as a layer in
   a network protocol (e.g. telnet, FTP).

   In the case of protocols where there is no concept of a
   session layer (e.g. UDP) or where sessions at the session
   layer are generally very short-lived (e.g. HTTP), virtual
   sessions are implemented by having each exchange between the
   user and the remote host include some form of cookie which
   stores state (e.g. a unique session ID, information about the
   user's preferences or authorisation level, etc.).

   See also login.

   2. A lasting connection using the session layer of a
   networking protocol.

   (1997-08-03)


Bouvier's Law Dictionary, Revised 6th Ed (1856):

SESSION. The time during which a legislative body, a court or other assembly
sits for the transaction of business; as, a session of congress, which
commences on the day appointed by the constitution, and ends when congress
finally adjourns before the commencement of the next session; the session of
a court, which commences at the day appointed by law, and ends when the
court finally rises a term.