See geezer in American Heritage Dictionary 4
Origin: Probably alteration of dialectal guiser, masquerader
Origin: , from Middle English gysar
Origin: , from gysen, to dress
Origin: , from gyse, guise, fashion; see guise. Word History: A relationship with a word we know well is disguised in the word geezer. A clue to this relationship is found in British dialect. The English Dialect Dictionary defines geezer as “a queer character, a strangely-acting person,” and refers the reader to guiser, “a mummer, masquerader.” The citations for guiser refer to practices such as the following: “People, usually children … go about on Christmas Eve, singing, wearing masks, or otherwise disguised,” the last word of this passage being the one to which geezer is related.
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