As defined: A s’more is a traditional nighttime campfire treat popular in the United States and Canada, consisting of a fire roasted marshmallow and a layer of chocolate sandwiched between two pieces of graham cracker. National S’mores Day is celebrated annually on August 10.

Wikipedia Report:
S’more is a contraction of the phrase “some more”. Although the exact origin of the treat is unclear, reports about scouts from as early as 1925 describe them.[3] One early published recipe for a S’more is found in a book of recipes published by the Campfire Marshmallows company in the 1920s [4] where it was called a “Graham Cracker Sandwich.” The text indicates that the treat was already popular with both Boy Scouts and Girl Scouts. In 1927, a recipe for “Some More” was published in Tramping and Trailing with the Girl Scouts.[5] The contracted term “S’more” appears in conjunction with the recipe in a 1938 publication aimed at summer camps.[6] A 1956 recipe uses the name “S’Mores,” and lists the ingredients as “a sandwich of two graham crackers, toasted marshmallow and 1/2 chocolate bar”. A 1957 Betty Crocker cookbook contains a similar recipe under the name of “S’mores.
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