Unexpansive, like John, Paul and George, but not Ringo (12)

I believe the answer is:

monosyllabic

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'unexpansive' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for monosyllabic that I've seen before include "Unexpansive" , "Like John, Paul, or George, but not Ringo" , "barely talking" , "like all but the first word in this clue" , "speaking briefly?" .)

I've seen this clue in The Telegraph.

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