G96 ἀδόκιμος adokimos (ad-ok'-ee-mos) adj.
1. unapproved, i.e. rejected
2. (by implication) worthless
{literally or morally}
[from G1 (as a negative particle) and G1384]... See More
KJV: castaway, rejected, reprobate
Occurs at least 7x in the bible, and the concept is taught more than the specific word usage.
Jeremiah 6:30 Reprobate silver shall men call them, because the LORD hath rejected them.
Romans 1:28 And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient;
2 Corinthians 13:5 Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates?
2 Corinthians 13:6 But I trust that ye shall know that we are not reprobates.
2 Corinthians 13:7 Now I pray to God that ye do no evil; not that we should appear approved, but that ye should do that which is honest, though we be as reprobates.
2 Timothy 3:8 Now as Jannes and Jambres withstood Moses, so do these also resist the truth: men of corrupt minds, reprobate concerning the faith.
Titus 1:16 They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate.