Crossword Genius

Old German wants no second extension to cell (4)

Ross

I believe the answer is:

axon

'extension to cell' is the definition.
(part of a nerve cell)

'old german wants no second' is the wordplay.
'old german' becomes 'saxon' (I've seen this before).
'wants no' is a deletion indicator.
'second' becomes 's' (common abbreviation).
'saxon' with 's' taken out is 'AXON'.

(Other definitions for axon that I've seen before include "extension in cell" , "Part of cell transmitting" , "Disabling headache" , "impulsive conductor" , "Bit of a nerve!" .)

I've seen this clue in The Times.
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