The Collaborative International Dictionary of English v.0.48:

Shelter \Shel"ter\, v. t. [imp. & p. p. Sheltered; p. pr. &
   vb. n. Sheltering.]
   1. To be a shelter for; to provide with a shelter; to cover
      from injury or annoyance; to shield; to protect.
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            Those ruins sheltered once his sacred head.
                                                  --Dryden.
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            You have no convents . . . in which such persons may
            be received and sheltered.            --Southey.
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   2. To screen or cover from notice; to disguise.
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            In vain I strove to cheek my growing flame,
            Or shelter passion under friendship's name. --Prior.
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   3. To betake to cover, or to a safe place; -- used
      reflexively.
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            They sheltered themselves under a rock. --Abp.
                                                  Abbot.
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Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "sheltering":
   covering, custodial, defensive, fostering, guardian, guarding,
   immunizing, parental, preventive, prophylactic, protecting,
   protective, safeguarding, screening, shielding, tutelary, vigilant,
   watchful