Castaway

CASTAWAY (ἀδόκιμος, G99, disapproved). The KJV tr. of adokimos (1 Cor 9:27). The word itself is simply dokimos, “tested and approved,” with alpha privative. It is from the verb, dokimazo, “test with a view to approval, prove by testing, approve after testing.” The adjective adokimos would mean “disapproved after testing, not standing the test,” hence, “disqualified, disapproved (for future reward)”; cf. the figure of a race in the context. Elsewhere it is rendered “rejected, reprobate” (Rom 1:28; 2 Cor 13:5-7; 2 Tim 3:8; Titus 1:16; Heb 6:8).

International Standard Bible Encyclopedia (1915)

This word is rendered "castaway" only in the King James Version: "I myself should be a castaway" ("rejected" the Revised Version (British and American), the American Standard Revised Version, 1Co 9:27). But the same word occurs a number of times usually translated "reprobate" (Ro 1:28; 2Co 13:5-7; 2Ti 3:8; Tit 1:16); "rejected" (Hebrews 6:8).