Complain about core of college course (5)

I believe the answer is:

bleat

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'complain' is the definition.
(I know that bleat is a more specific form of complain)

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for bleat that I've seen before include "Sound sheepish" , "Cry of animal" , "Whine" , "Sound made by goat" , "Cry of a lamb at table" .)

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

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