A s'more is a traditional campfire treat popular in the United States and Canada, consisting of a roasted marshmallow and a layer of chocolate sandwiched between two pieces of graham cracker. The name "s'more" means "some more", as in: "give me some more!".
S'more appears to be a contraction of the phrase, "some more". The informal nature of this term reflects the environment in which s'mores are traditionally served and its meaning hints at the desires of campers who are not satisfied by just one s'more. Some have jokingly surmised that the name originated from people who were so busy eating the tasty treat that they did not have time to speak in complete sentences, or alternately, that their enunciation was compromised by the fact that their mouth was still full of the previously mentioned s'more.
Another theory is that the dessert is so sticky, particularly due to the combination of melted chocolate and marshmallow, that it is especially difficult to talk or swallow, and this remains the case for some time even after the entire dessert is eaten. Therefore, if someone who has finished swallowing their last piece of the dessert is asked if they'd like another, "s'more please" would be all they could manage to relay.
While the origin of this popular campfire dessert is unclear, the first recorded version of the recipe can be found in the Girl Scout Handbook of 1927. The recipe is credited to ...