From hettao; a deterioration, i.e. (objectively) failure or (subjectively) loss -- diminishing, fault.
see GREEK hettao
1. a diminution, decrease: i. e. defeat, Isaiah 31:8; αὐτῶν, brought upon the Jewish people in that so few of them had turned to Christ, Romans 11:12 (R. V. loss).
2. loss, namely, as respects salvation, 1 Corinthians 6:7 (R. V. text defect). Cf. Meyer (but cf. his 6te Aufl.) on each passage. (Elsewhere only in ecclesiastical writ:)