That German’s back again (4)

I believe the answer is:

otto

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'that german's' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for otto that I've seen before include "Essential oil from flowers - German boy's name" , "Palindromic German male Christian name" , "perfume ingredient" , "A man" , "Swiss perhaps" .)

I've seen this clue in the Evening Standard.

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