The Collaborative International Dictionary of English v.0.48:

Entanglement \En*tan"gle*ment\, n.
   1. State of being entangled; intricate and confused
      involution; that which entangles; intricacy; perplexity.
      [1913 Webster]

   2. (Mil.) An extensive low obstacle formed of stakes, stumps,
      or the like, connected by wires, ropes, or the like.
      [Webster 1913 Suppl.]

   3. (Naut.) An obstruction of cables and spars across a river
      or harbor entrance.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

entanglement
    n 1: an intricate trap that entangles or ensnares its victim
         [syn: web, entanglement]

Moby Thesaurus II by Grady Ward, 1.0:

146 Moby Thesaurus words for "entanglement":
   abatis, absorption, adulterous affair, adultery, advanced work,
   affair, amour, association, balistraria, bamboozlement, bank,
   banquette, barbed-wire entanglement, barbican, barricade, barrier,
   bartizan, bastion, battlement, befooling, bluffing, breastwork,
   bulwark, calculated deception, casemate, cheval-de-frise,
   circumvallation, circumvention, cobweb, complexity, complexness,
   complication, conning, contact, contravallation, convolution,
   counterscarp, crabbedness, cuckoldry, curtain, deceiving,
   deception, deceptiveness, defrauding, delusion, delusiveness,
   demibastion, dike, drawbridge, dupery, earthwork, embarrassment,
   embroilment, enclosure, engagement, enmeshment, ensnarement,
   entrapment, escarp, escarpment, eternal triangle, fallaciousness,
   fallacy, falseness, fence, fieldwork, flimflam, flimflammery,
   flirtation, fond illusion, fooling, forbidden love, fortalice,
   fortification, glacis, hallucination, hanky-panky, hoodwinking,
   illicit love, illusion, implication, inclusion, infidelity,
   intricacy, intricateness, intrigue, involution, involvement,
   kidding, liaison, loophole, love affair, lunette, machicolation,
   mantelet, merlon, meshes, mirage, mound, outwitting, outwork,
   overreaching, palisade, parados, parapet, perplexity, phantasm,
   portcullis, postern gate, putting on, ramification, rampart,
   ravelin, redan, redoubt, relation, romance, romantic tie,
   sally port, scarp, sconce, self-deception, snow job,
   song and dance, spoofery, spoofing, stockade, subterfuge, subtlety,
   swindling, tanglement, technicality, tenaille, toils, triangle,
   trickiness, tricking, unfaithfulness, vallation, vallum,
   victimization, vision, web, willful misconception,
   wishful thinking, work