[1] : The Collaborative International Dictionary of English v.0.48

intrusive \intru"sive\, a.
   apt to intrude; characterized by intrusion; entering without
   right or welcome.
   1913 webster

   intrusive rocks geol., rocks which have been forced,
      while in a plastic or melted state, into the cavities or
      between the cracks or layers of other rocks. the term is
      sometimes used as equivalent to plutonic rocks. it is
      then contrasted with effusive or volcanic rocks. --
      intru"sively, adv. -- intru"siveness, n.
      1913 webster
see also:
intrusive rocks plutonic rocks intru"sively intru"siveness 

[2] : WordNet (r) 2.0

intrusive
     adj 1: tending to intrude especially upon privacy; "she felt her
            presence there was intrusive" ant: unintrusive
     2: of rock material; forced while molten into cracks between
        layers of other rock ant: extrusive
     3: thrusting inward; "an intrusive arm of the sea" ant: protrusive
see also:
unintrusive extrusive protrusive 

[3] : Moby Thesaurus II by Grady Ward, 1.0

97 moby thesaurus words for "intrusive":
   alien, barbarian, barbaric, barbarous, busy, entering, exotic,
   exterior, external, extraneous, extraterrestrial, extrinsic,
   foreign, foreign-born, forward, frantic, frenetic, frenzied,
   hectic, hyperactive, hyperkinetic, ill-considered, ill-seasoned,
   ill-timed, importunate, improper, in, inappropriate, inauspicious,
   inbound, incoming, inconvenient, inexpedient, infelicitous,
   inflooding, inflowing, ingoing, ingressive, inopportune, inpouring,
   inquisitive, intempestive, interfering, interruptive, intervenient,
   intruding, invasive, inward, inward-bound, irrelevant, irruptive,
   late, mal a propos, malapropos, meddlesome, meddling, mistimed,
   nosy, obtrusive, off base, officious, out of line, out of phase,
   out of time, outland, outlandish, outside, premature, presumptuous,
   prying, pushy, snoopy, strange, too late, too soon, ulterior,
   unbefitting, uncalled-for, unearthly, unfavorable, unfit,
   unfitting, unfortunate, unhandy, unhappy, unlucky, unpropitious,
   unready, unripe, unseasonable, unsought, unsuitable, untimely,
   untoward, unwanted, unwelcome, wrong

Intrusive >> I Words
Intrusive, definition of term: Intrusive
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