Law scholar losing time in talk (5)

I believe the answer is:

rabbi

'law scholar' is the definition.
(scholar in Jewish law)

I cannot understand how the remainder of the clue works.

(Other definitions for rabbi that I've seen before include "Teacher of Jewish law" , "Sacks, for example" , "Jewish learned man" , "legal scholar" , "Spiritual leader of a Jewish congregation" .)

I've seen this clue in The Times and The Sun.

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