The Collaborative International Dictionary of English v.0.48:

Hallow \Hal"low\ (h[a^]l"l[-o]), v. t. [imp. & p. p.
   Hallowed(-l[-o]d); p. pr. & vb. n. Hallowing.] [OE.
   halowen, halwien, halgien, AS. h[=a]lgian, fr. h[=a]lig holy.
   See Holy.]
   To make holy; to set apart for holy or religious use; to
   consecrate; to treat or keep as sacred; to reverence.
   "Hallowed be thy name." --Matt. vi. 9.
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         Hallow the Sabbath day, to do no work therein. --Jer.
                                                  xvii. 24.
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         His secret altar touched with hallowed fire. --Milton.
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         In a larger sense . . . we can not hallow this ground
         [Gettysburg].                            --A. Lincoln.
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WordNet (r) 3.0 (2006):

hallow
    v 1: render holy by means of religious rites [syn: consecrate,
         bless, hallow, sanctify] [ant: deconsecrate,
         desecrate, unhallow]