Webster's Revised Unabridged Dictionary · 1913

Shamefaced

Shamefaced , adjective

[For shamefast; Anglo-Saxon scamfaest. See Shame, n., and Fast firm.]

Easily confused or put out of countenance; diffident; bashful; modest.
Your shamefaced virtue shunned the people's prise. — Dryden

Shamefaced was once shamefast, shamefacedness was shamefastness, like steadfast and steadfastness; but the ordinary manifestations of shame being by the face, have brought it to its present orthography. Trench.