A minor related mention; made as an aside, or afterthought.(noun)
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Use "sidenote" in a sentence
"The answer to the sidenote is a heartfelt "yes, of course!""
"Write a post, and wrap the text that you want to highlight in span tags with the class "sidenote" and a title attribute."
"That's on the beach though and has nothing to do with the city of Colima but serves as a sidenote for considering beach towns if one is particular about sharing their bed."