The Collaborative International Dictionary of English v.0.48:

Shamefast \Shame"fast\, a. [AS. scamf[ae]st.]
   Modest; shamefaced. -- Shame"fast*ly, adv. --
   Shame"fast*ness, n. [Archaic] See Shamefaced.
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         Shamefast she was in maiden shamefastness. --Chaucer.
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         [Conscience] is a blushing shamefast spirit. --Shak.
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         Modest apparel with shamefastness.       --1 Tim. ii. 9
                                                  (Rev. Ver.).
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