What does the phrasal verb 'put off' mean? Is it an idiom?

[dina]

Test No. incompl/inter-72 "How to encourage", question 10

You mustn't ever be ......... off by a few setbacks.

(a) taken
(b) held
(c) put
(d) pushed

Test No. incompl/inter-72 "How to encourage", answer 10

You mustn't ever be put off by a few setbacks.

Correct answer: (c) put

Your answer was: incorrect
You mustn't ever be pushed off by a few setbacks.
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hello,

Please explain the meaning of put off

Thanks

[Torsten]

If you are put off by something it brings you down, it discourages you.

TOEFL listening lectures: A university lecture on Modern World History