Beer mug for chef Rick (5)

I believe the answer is:

stein

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'beer mug' is the definition.
(synonyms)

I don't understand the remainder of the clue.

(Other definitions for stein that I've seen before include "Inset into earthenware mug for beer" , "Gertrude __, avant-garde US author, d. 1946" , "German earthenware beer mug" , "German tankard" , "Glass" .)

I've seen this clue in The Sun.

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