Endless memos stir dons' agitation of mind (7)

I believe the answer is:

emotion

I'm a little stuck... Click here to teach me more about this clue!

'agitation of mind' is the definition.
(I've seen this before)

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

(Other definitions for emotion that I've seen before include "Hatred or love, say" , "Feeling - sentiment" , "sense" , "Fear possibly" , "Strong desire" .)

I've seen this clue in The Telegraph.

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