confident (adj.)

1570s, "self-reliant, sure of oneself;" c. 1600, "fully assured, having strong belief," from French confident, from Latin confidentem (nominative confidens) "firmly trusting, reliant, self-confident, bold, daring," present participle of confidere "to have full trust or reliance," from assimilated form of com, here perhaps an intensive prefix (see com-), + fidere "to trust" (from PIE root *bheidh- "to trust, confide, persuade"). Related: Confidently.