Source : Webster's Revised Unabridged Dictionary (1913)

Encroach \En*croach"\, v. i. [imp. & p. p. {Encroached}; p. pr.
   & vb. n. {Encroaching}.] [OF. encrochier to perch, prop., to
   hook, fasten a hook (perh. confused with acrochier, F.
   accrocher, to hook, get hold of, E. accroach); pref. en- (L.
   in) + F. croc hook. See {Crook}, and cf. {Accroach}.]
   To enter by gradual steps or by stealth into the possessions
   or rights of another; to trespass; to intrude; to trench; --
   commonly with on or upon; as, to encroach on a neighbor; to
   encroach on the highway.

         No sense, faculty, or member must encroach upon or
         interfere with the duty and office of another. --South.

         Superstition, . . . a creeping and encroaching evil.
                                                  --Hooker.

         Exclude the encroaching cattle from thy ground.
                                                  --Dryden.

   Syn: To intrude; trench; infringe; invade; trespass.

Source : WordNet®

encroaching
     adj : gradually intrusive without right or permission; "we moved
           back from the encroaching tide"; "invasive tourists";
           "trespassing hunters" [syn: {encroaching(a)}, {invasive},
            {trespassing(a)}]