English Master’s ditched by doubtful fellow showing spirit (5)

I believe the answer is:

ethos

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'spirit' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for ethos that I've seen before include "Characteristic spirit (of a culture, etc)" , "Those (anag.)" , "Spirit of a culture/age" , "Distinctive attitude (of culture, person etc)" , "Distinctive group spirit" .)

I've seen this clue in The Times.

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