The Collaborative International Dictionary of English v.0.48:

Bolster \Bol"ster\, v. t. [imp. & p. p. Bolstered; p. pr. &
   vb. n. Bolstering.]
   1. To support with a bolster or pillow. --S. Sharp.
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   2. To support, hold up, or maintain with difficulty or
      unusual effort; -- often with up.
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            To bolster baseness.                  --Drayton.
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            Shoddy inventions designed to bolster up a
            factitious pride.                     --Compton
                                                  Reade.
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