The Collaborative International Dictionary of English v.0.48:

Junction \Junc"tion\, n. [L. junctio, fr. jungere, junctum, to
   join: cf. F. jonction. See Join.]
   [1913 Webster]
   1. The act of joining, or the state of being joined; union;
      combination; coalition; as, the junction of two armies or
      detachments; the junction of paths.
      [1913 Webster]

   2. The place or point of union, meeting, or junction;
      specifically, the place where two or more lines of railway
      meet or cross.
      [1913 Webster]

   Junction plate (Boilers), a covering or break-join plate
      riveted to and uniting the edges of sheets which make a
      butt joint.

   Junction rails (Railroads), the switch, or movable, rails,
      connecting one line of track with another.
      [1913 Webster]

WordNet (r) 3.0 (2006):

junction
    n 1: the place where two or more things come together
    2: the state of being joined together [syn: junction,
       conjunction, conjugation, colligation]
    3: the shape or manner in which things come together and a
       connection is made [syn: articulation, join, joint,
       juncture, junction]
    4: something that joins or connects [syn: junction,
       conjunction]
    5: an act of joining or adjoining things [syn: junction,
       adjunction]

Moby Thesaurus II by Grady Ward, 1.0:

310 Moby Thesaurus words for "junction":
   Anschluss, L, abutment, abuttal, access, accession, accompaniment,
   accord, accordance, accretion, addition, adherence, adhesion,
   adjacency, adjoiningness, adjunct, adjunction, affairs,
   affiliation, affinity, affixation, agglomeration, agglutination,
   aggregation, agreement, aisle, alley, alliance, amalgamation,
   ambulatory, annexation, aperture, apposition, approximation,
   appulse, arcade, artery, articulation, assemblage, assembly,
   assimilation, association, attachment, augmentation, avenue, blend,
   blending, bond, bracketing, branch, building, buildup, cabal,
   cable railway, cahoots, call-up, canvass, cartel, census,
   centralization, channel, cling, clinging, cloister, closeness,
   clotting, clustering, co-working, coaction, coagulation,
   coalescence, coalition, cog railway, coherence, cohesion,
   cohesiveness, coincidence, collaboration, collection, collectivity,
   colligation, collocation, collusion, colonnade, combination,
   combine, combined effort, combo, communication, compaction,
   comparison, composition, compound, concatenation, concert,
   concerted action, concomitance, concordance, concourse, concretion,
   concurrence, condensation, conduit, confederacy, confederation,
   confluence, conflux, congealment, congelation, congeries,
   conglobation, conglomeration, congregation, conjoining,
   conjugation, conjunction, connectedness, connection, consilience,
   consolidation, conspiracy, constitution, construction,
   conterminousness, contiguity, contrariety, convergence,
   cooperation, copulation, corralling, correspondence, corridor,
   coterminousness, coupling, covered way, crossroads, data-gathering,
   dealings, deduction, defile, disjunction, ecumenism, el,
   electric railway, elevated, elevated railway, embankment,
   embodiment, encompassment, enosis, exit, fabrication, fashioning,
   federalization, federation, feeder, feeder line, ferry, filiation,
   ford, formation, fusion, gallery, gathering, getup,
   gravity-operated railway, homology, hookup, horse railway,
   inclusion, incorporation, increase, ingathering, inlet,
   inseparability, integration, interchange, intercommunication,
   intercourse, interlinking, intersection, intimacy, inventory,
   joinder, joining, jointure, junction, juncture, junta,
   juxtaposition, knotting, lane, league, liaison, light railroad,
   line, link, linkage, linking, main line, make, makeup, marriage,
   meeting, meld, melding, merger, merging, metro, mixture,
   mobilization, monorail, muster, mutual attraction, nearness,
   opening, organization, outlet, overpass, package, package deal,
   pairing, parasitism, pass, passage, passageway, perigee,
   perihelion, piecing together, portico, prefixation, propinquity,
   proximity, putting together, rack railway, rack-and-pinion railway,
   rail, rail line, railroad, railroad tunnel, railway, rapport,
   reinforcement, relatedness, relation, relations, relationship,
   roadbed, roadway, rodeo, roundup, saprophytism, seam, set, setup,
   shaping, sidetrack, siding, similarity, simultaneity,
   solidification, splice, sticking, street railway, streetcar line,
   structure, structuring, subway, suffixation, superaddition,
   superfetation, superjunction, superposition, supplementation,
   survey, switchback, symbiosis, sympathy, synchronism, syncretism,
   syndication, syneresis, synergy, synthesis, syzygy, terminal,
   terminus, tie, tie-in, tie-up, track, traject, trajet, tram,
   tramline, trestle, trolley line, trunk, trunk line, tube, tunnel,
   turnout, underground, underpass, unification, union, united action,
   uniting, wedding, yoking



U.S. Gazetteer Places (2000):

Junction, IL -- U.S. village in Illinois
   Population (2000):    139
   Housing Units (2000): 75
   Land area (2000):     0.887141 sq. miles (2.297684 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.887141 sq. miles (2.297684 sq. km)
   FIPS code:            38778
   Located within:       Illinois (IL), FIPS 17
   Location:             37.722726 N, 88.237973 W
   ZIP Codes (1990):     62954
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Junction, IL
    Junction


U.S. Gazetteer Places (2000):

Junction, TX -- U.S. city in Texas
   Population (2000):    2618
   Housing Units (2000): 1222
   Land area (2000):     2.286429 sq. miles (5.921824 sq. km)
   Water area (2000):    0.006923 sq. miles (0.017931 sq. km)
   Total area (2000):    2.293352 sq. miles (5.939755 sq. km)
   FIPS code:            38248
   Located within:       Texas (TX), FIPS 48
   Location:             30.489772 N, 99.771335 W
   ZIP Codes (1990):     76849
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Junction, TX
    Junction


U.S. Gazetteer Places (2000):

Junction, UT -- U.S. town in Utah
   Population (2000):    177
   Housing Units (2000): 104
   Land area (2000):     14.380676 sq. miles (37.245777 sq. km)
   Water area (2000):    0.579905 sq. miles (1.501948 sq. km)
   Total area (2000):    14.960581 sq. miles (38.747725 sq. km)
   FIPS code:            39590
   Located within:       Utah (UT), FIPS 49
   Location:             38.236403 N, 112.222961 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Junction, UT
    Junction