Failed vs Flunk - What's the difference?

As verbs the difference between failed and flunk

is that failed is past tense of fail while flunk is of a student, to fail a class; to not pass.

(head)

(fail)

* unfailed

(en verb)

(US, ambitransitive) Of a student, to fail a class; to not pass.

He flunked math, again.

(US) Of a teacher, to deny a student a passing grade.

Unsatisfied with Fred's progress, the teacher flunked him.

(US, dated, informal) To shirk (a task or duty).

To back out through fear.