[comedy]. The Greek comic actors used to wear a sandal and sock. The difference between the sock and the tragic buskin was this- the sock went only to the ankle, but the buskin extended to the knee. (See Buskin.)
Then to the well-trod stage anon, If Jonson's learned sock be on.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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