Synonyms for Shamefaced (same or very similar meaning)
WordNet sense 1 (not offensive to sexual mores in conduct or appearance):
modest
WordNet sense 2 (showing a sense of shame):
sheepish
WordNet sense 3 (showing a sense of guilt):
guilty, hangdog, shamed
WordNet sense 4 (feeling shame or guilt or embarrassment or remorse):
ashamed
From the ODE community, based on WordNet
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