The Collaborative International Dictionary of English v.0.48:

accroach \ac*croach"\ ([a^]k*kr[=o]ch"), v. t. [OE. acrochen,
   accrochen, to obtain, OF. acrochier, F. accrocher; [`a] (L.
   ad) + croc hook (E. crook).]
   1. To hook, or draw to one's self as with a hook. [Obs.]
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   2. To usurp, as jurisdiction or royal prerogatives.
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            They had attempted to accroach to themselves royal
            power.                                --Stubbs.
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