From akathartos; impurity (the quality), physically or morally -- uncleanness.
see GREEK akathartos
a. physical: Matthew 23:27.
b. in a moral sense, the impurity of lustful, luxurious, profligate living: Romans 1:24; Romans 6:19; 2 Corinthians 12:21; Galatians 5:19; Ephesians 4:19; Ephesians 5:3; Colossians 3:5; 1 Thessalonians 4:7; used of impure motives in 1 Thessalonians 2:3. (Demosthenes, p. 553, 12.) Cf. Tittmann i., p. 150f.