What does 'back down' mean? Is it a phrasal verb?

[kentavr]

Test No. incompl/inter-25 "Wrapped round her finger", question 3

He is such a coward because whenever it comes to speaking his mind he always ......... down instead.

(a) backs
(b) heads
(c) hands
(d) noses

Test No. incompl/inter-25 "Wrapped round her finger", answer 3

He is such a coward because whenever it comes to speaking his mind he always backs down instead.

Correct answer: (a) backs

Your answer was: n/a
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What does it mean back down?

[Torsten]

If you back down on something, you accept someone else's point of view or agree to do what they want you to do. You give in.

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