To make indistinct as if by rubbing: "Five years' absence had done nothing to efface the people's memory of his firmness"(Alan Moorehead). See Synonyms at erase.
To conduct (oneself) inconspicuously: "When the two women went out together, Anna deliberately effaced herself and played to the dramatic Molly"(Doris Lessing).
[Middle English effacen, from French effacer, from Old French esfacier : es-, out (from Latin ex-, ex-) + face, face; see face.] ef·face'a·ble adj., ef·face'ment n., ef·fac'er n.