The Collaborative International Dictionary of English v.0.48:

Sunder \Sun"der\, v. t. [imp. & p. p. Sundered; p. pr. & vb.
   n. Sundering.] [OE. sundren, AS. sundrain (in [=a]sundrain,
   gesundrain), from sundor asunder, separately, apart; akin to
   D. zonder, prep., without, G. sonder separate, as prep.,
   without, sondern but, OHG. suntar separately, Icel. sundr
   asunder, Sw. & Dan. s["o]nder, Goth. sundr[=o] alone,
   separately.]
   To disunite in almost any manner, either by rending, cutting,
   or breaking; to part; to put or keep apart; to separate; to
   divide; to sever; as, to sunder a rope; to sunder a limb; to
   sunder friends.
   [1913 Webster]

         It is sundered from the main land by a sandy plain.
                                                  --Carew.
   [1913 Webster]