Rabelais hasn't got ear of Herb (5)

I believe the answer is:

basil

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'herb' is the definition.
(basil is a kind of herb)

I cannot understand how the rest of the clue works.

(Other definitions for basil that I've seen before include "Aromatic herb with purplish-green leaves" , "Herb of mint family" , "Herb (from Fawlty Towers?)" , "A herb; Cardinal --- Hume" , "Plant; Brush; Fawlty" .)

I've seen this clue in the Irish Times.

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