Eccentric chap, a Welshman (8)

I believe the answer is:

cambrian

'a welshman' is the definition.

'eccentric chap' is the wordplay.
'eccentric' becomes 'cam' (an eccentric is a mechanical device such as a cam).
'chap' becomes 'brian' (**).
'cam'+'brian'='CAMBRIAN'

(Other definitions for cambrian that I've seen before include "Characteristic of Wales or its people" , "Geological period" , "Relating to Wales" , "Welsh" .)

I've seen this clue in The Times.

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