Eccentric testimonial (9)

I believe the answer is:

character

I believe this is a double definition.

'eccentric' is the first definition.
('character' can be a synonym of 'eccentric')

'testimonial' is the second definition.
(character is a kind of testimonial)

(Other definitions for character that I've seen before include "Distinctive nature" , "Nature; good reputation" , "Role - nature" , "eccentric individual" , "Stamp < letter" .)

I've seen this clue in The Guardian.

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