3 occurrences across the corpus

KJV Apocrypha (Catholic Deuterocanon)

Sirach (Ecclesiasticus) 37:11

Neither consult with a woman touching her of whom she is jealous; neither with a coward in matters of war; nor with a merchant concerning exchange; nor with a buyer of selling; nor with an envious man of thankfulness; nor with an unmerciful man touching kindness; nor with the slothful for any work; nor with an hireling for a year of finishing work; nor with an idle servant of much business: hearken not unto these in any matter of counsel.

OT Pseudepigrapha

4 Maccabees 5:36

But he said unto them, 'For me ye have no fire so exceeding hot as to make me a coward.

4 Maccabees 6:35

None of the seven youths turned coward, none shrunk in the face of death, but all hastened to the death by torture as if running the road to immortality.