Akademik

О-45
ЗАБЛУДШАЯ ОВЦА (ОВЁЧКА) lit NP usu sing) a person who has strayed from a righteous way of life: lost sheep sheep that has gone astray.
From the Bible (Matt. 18:12, Luke 15:4-6).

Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. . 2004.