The Oxford Thesaurus An A-Z Dictionary of Synonyms - shamefacedadj.

1) bashful, shy, modest, self-effacing, diffident, timid, meek, coy, sheepish, timorous: He felt shamefaced as a schoolboy when they awarded him a medal for bravery. 2) ashamed, shamed, abashed, embarrassed, humiliated, dishonoured, mortified, humbled, chastened, chagrined, uncomfortable, discomfited, remorseful, red-faced: Shamefaced, she finally admitted the truth about where she had been.